GB2457818A - Identifying a particular signal on a CAN bus - Google Patents

Abstract

An apparatus 1002, for identifying a signal from a plurality of other signals transmitted on a vehicle network bus 1000, comprises: means 1003 arranged to monitor the bus in a first period of time and a second, different, period of time and observe any signals transmitted on the bus in those periods, wherein in the first period it is highly likely that the signal to be identified is not being transmitted whilst in the second period of time the signal to be identified is generated on the bus; means 1009 arranged to cause the device 1007 to generate the signal in the second period of time; and means 1006 to compare signals observed in the first and second periods so as to identify the signal. The apparatus may be used in configuring a gateway unit as part of a Controller Area Network (CAN) on a vehicle modified e.g. for disabled drivers, which can accept signals from a device 1007 (e.g. a steering-wheel mounted keypad) which perform the same functions as a different device (e.g. a stalk switch on the steering column).

Description

IMPROVEMENTS RELATING TO DEVICES OPERATING ON A

VEHICLE NETWORK BUS

This invention relates to identifying signals sent on a vehicle network bus from a particular device and using these identified signals when configuring additional operating devices for retrofitting to a vehicle, for example when the vehicle is modified for disabled use. It in particular it relates to vehicles which use a CAN bus to connect a driver control to vehicle peripherals.

It is known to provide a vehicle with a stalk switch that allows the driver easy access to a range of devices within reach of the steering wheel.

Ideally the functions controlled by the stalk can be operated without moving the hands from the wheel simply by moving the stalk with the fingertips. Commonly this is used to operate the vehicles indicators by moving the stalk up or down to indicate left or right (depending on which side of the steering column the stalk is mounted it may be moved up or down to indicate left). Typically the column stalk comprises a multi-way switch enabling it to be moved in additional directions to give control of more functions. For example it can sometimes be arranged that rotating part of the stalk turns the lights on or off or perhaps operates the vehicle wiper blades. Indeed a stalk may be provided which does not control the .. indicators but controls other functions instead. Whenever the stalk is S.., * moved a switch that is associated with the direction of movement may be opened or closed.

Every year, up to 8000 vehicles in the UK are modified for use by people ". : who cannot use the conventional controls. Conversions are often tailored S ** to the individual and the vehicle and can vary dramatically. One common type of conversion is particularly apt for users who are unable to use both hands to control the vehicle. For example a very common conversion is for people for cannot use their legs to operate a conventional brake pedal of throttle and may therefore have only one hand available for steering whilst the other is controlling the accelerator and brake. In these cases the conversion may include modifying the steering wheel and providing an alternative method of operating the stalk controls.

The steering wheel can be modified by adding a knob or grip to the wheel making it easier to turn with one hand. It is clear that when gripping the wheel in this way it is not possible to operate the regular column stalks.

To ameliorate this whilst still enabling the functions controlled by the stalk to be operated an additional control device may be provided which is fixed to the wheel close to the knob or grip. The functionality of the stalk controls may be passed to this additional control.

In one arrangement the control may comprise a small keypad 3 that is located next to the grip 9 on the steering wheel 4. Pressing a key on the keypad 3 controls one of the respective functions associated with the column stalk controls 6 (there are two stalks in this example both replaced by one keypad). For instance, pressing one button may cause the vehicle to indicate left and a different button may cause it to indicate right.

In a simple arrangement, the keypad 3 may be connected wirelessly via an infrared signal 2 from a transmitter 5 sent to a receiver 1 and on through * wires 9 to a relay box 8. This relay box receives signals from the keypad 25 3 and uses these to open and close one or more relays which are **.

* connected through further wires 7 across the switches in the stalk controls 6. Thus, when the relay is closed it provides the same effect as moving *. : the stalk. * **

This type of modification is shown in Figure 2 of the accompanying drawings. For each function of the stalk a relay is provided. One relay in the box 8 is shown connected by wire 7 to either side of a respective switch of the control stalk unit 6 that is opened and closed by moving the stalk controls. The connection is usually made by locating and splicing the correct wires that enter and leave the stalk unit. This is seen in Figure 2 with the boundaries of the stalk control unit 6 marked by the box on the left side of the figure.

The applicant has appreciated that this solution cannot be used when there is no direct electrical connection between the stalk control and the peripheral. By this we mean that the stalk does not control the peripheral simply by opening and closing a switch in an electrical cable connected directly to the peripheral. With such a system a clearly identifiable and conveniently accessible length of wire which can be connected to a relay may be impossible to find or hard to access.

Non-direct connection is becoming more common where the vehicle includes a bus such as a CAN bus and the stalk provides operational inputs to a node of the bus through a controller/host processor provided at the node. Here the operation of the stalk merely indicates the driver's intent, with a signal later being generated and sent across the bus which encodes a message that gives instructions to the device being operated.

For instance the state of the column stalk switches may be transmitted over the CAN bus via a small microcontroller within the column stalk . * , area. The control is achieved by other ECU's within the vehicle that receive the column stalk CAN message that indicates the state of the * column stalk controls and therefore the drivers request. All initial processing may take place within the stalk unit itself which is often part of an integrated circuit sealed within a housing. This is shown schematically in Figure 4 of the accompanying drawings, the stalk including a column stalk ECU. Where useful the same reference numerals have been used as Figures 1 and 2 to show functionally equivalent parts.

An object of the present invention is to provide a device suitable for modifying a vehicle which has stalk controls that transmit messages across a network bus to enable that vehicle to be operated by a driver who is unable to operate the conventional stalks or has a preference for operating the devices controlled by the stalk in a different manner. In a further object the invention may also extend to providing a device which enables a vehicle to be modified so that a driver can operate other controls-not necessarily related to the steering function-from the device.

According to a first aspect, therefore, there is provided a supplemental operating device for use in modifying a vehicle which functions as an alternative device for operating one or more vehicle ancillary functions otherwise operated by at least one main user operable input device mounted on the vehicle of the kind which transmits messages for transmission across a network bus of a vehicle to which it is fitted, the supplemental device comprising: an additional user operable input device which includes at least one user operable input means which can be operated by the driver to select a function, the additional input device also including signal generating means for generating a signal responsive to operation of the input means; * *. and ** * *::::* a gateway controller unit which receives the signals from the user * * operable input means and determines from the signals the operation of the additional user operable input device, and in which said a gateway controller unit further includes a second input port for receiving a signal output from the main user operable *. device which the additional control device is an alternative to, and a third * *_.

port through which the gateway controller unit may be connected to the network bus of the vehicle, the controller supplying bus messages to the network through the third port in response to operation of either the main device or additional device such that operation of the additional device causes the same messages to the transmitted through the third port as operation of a corresponding function on the main device.

The at least one main user operable input device may comprise a column stalk unit which is fixed to, or next to or otherwise forms part of a steering column assembly.

Alternatively it may comprise a joystick or be attached to a joystick fitted to the vehicle and which joystick controls the throttle and/or brakes of the vehicle. It is known to provide a joystick to control throttle/brake through a direct mechanical linkage to the throttle and brake cylinder (in a similar manner to a dual control vehicle) and the applicant has appreciated that this would be a good place to provide the device of the present invention as it will fall easily to hand.

The location of the gateway controller between the main device and additional user operable input device and the network enables the additional device to offer the same functionality to the driver that the main user operable device offers, but depending on its format may permit a different method of input, different location etc. The additional device may supplement a main device that is associated with a steering CAN bus ECU, such as indicator stalk signals. * * * S. * S...

It may alternatively or additionally provide signals onto the bus that are * .. associated with a different CAN bus ECU that is associated with functions * * * that are not related to steering. For instance, it may issue control signals for throttle and/or braking. Where throttle and braking signals are passed over a CAN bus, the device could be used as an alternative to a 30 traditional joystick and eliminate the need for a mechanical linkage.

The additional user operable input device may comprise one or more keypads, footpads, or may be responsive to voice commands, mouth movements etc. It may include one or more buttons, levers, switches or knobs. When operated each button, lever etc may cause a unique (to that button or knob) signal to be generated from which the gateway controller unit can determine which button or lever etc has been operated. The gateway controller unit may be preconfigured (or user configurable) such that any function that could be operated by the stalk can be operated by one of the buttons or levers.

The additional user operable device may include a transmitter and the gateway unit may include a receiver, the transmitter and receiver together enabling signals generated by the additional device to be sent wirelessly to the gateway unit. Eliminating wires gives great flexibility to the location of the supplemental device. For instance it my be mounted onto the steering wheel or close to it, whilst the gateway ECU is mounted remote from the wheel or otherwise further from it.

Alternatively, the user device may be hardwired to the gateway unit as a means to enable signals from the user device to be fed to the second input port.

The transmitter may comprise a wireless transmitter that may emit S...

.. : optical, infrared, radiowave, microwave or long wave radiation. Other S...

25 forms of transmitter may be provided, perhaps even relying on transmitting audible signals.

S S..

The gateway controller unit may be arranged so that any messages it receives from the main device (e.g. a stalk unit) are replaced by, : 30 modified by or supplemented with messages derived from the signals received at the first input port.

The supplemental user operating device may therefore supply at its third port signals compatible with a vehicle bus network which includes one or more of: messages it has received from a stalk unit (main device) and which are unmodified; messages it has received from the stalk unit (main device) which are modified by the gateway controller as a function of the signal received at the first port from the supplemental device; and new messages generated by the gateway controller unit from the signal received at the first input port which mimics messages from the main device.

Where messages received from the main device (e.g. a stalk unit) are sent to the network bus the driver has the choice of operating either the stalk or the new supplemental device.

By mimicking signals or messages from the main device (e.g. the stalk) we mean that any device connected to the bus which is intended to receive messages from the stalk cannot distinguish a message from the stalk that has not been modified from a message which has been modified by or generated by the gateway controller unit. This ensures the modification is transparent to the devices that the stalk controls and so ensures that error messages are not generated by those devices as they may if they detect a S...

25 change. * *1 * * S

Where the main device (for example the stalk) generates periodic messages the gateway controller unit may be arranged so as to send periodic signals to the third (vehicle network) port that includes the *.. 30 signals types "no request made" or "request made" which allows for errors to be identified in the operation of the additional device by other devices connected to the bus which are expecting to receive such messages. In the event that the messages are not received the device waiting for them may return an error message. The controller unit may automatically detect the periodicity of the stalk controller message during an installation process or it may generate them as appropriate in response to periodic messages it receives from a stalk.

The gateway controller unit may include an electrical connection directly between the second input port (connected to the main device such as a stalk controller) and the output port (connected to the vehicle network) which is normally open and which can be closed in the event that an error message is received by the additional control device at its output port.

This direct connection may be opened and closed by one or more relays.

When closed the additional user operable device will be prevented from replacing or modifying signals from the main device and will disable functioning of the additional user operable input device. A main device such as a stalk unit connected to the input port will be connected through the gateway controller unit directly to a bus connected at the output port.

The additional control device may be configured to receive signals and to output signals that are compatible with vehicles that have a CAN bus or any other network bus that uses some other protocol such as K-Line, LIN, Flexray, RS232 etc. The CAN type of bus is well known and uses a S..

simple twisted wire pair to carry signals from a control device such as a S...

stalk to a controlled device such as an electrical ancillary, e.g. an indicator.

S S..

The additional user operable input device may generate binary coded signals which are unique for each of its input means, e.g. 001 for button *: 30 1, 010 for button 2 etc. The gateway may assign messages to each binary coded signal so that when it receives a given signal on its first input port it causes the stored message to be output at its third port.

To function with a CAN bus the second port may comprise two terminals, one for each end of a length of twisted pair from a stalk unit or node. The third port may also comprise a pair of terminals with one for each end of a length of twisted wire pair for connection to the controlled device across the rest of the CAN bus.

The gateway ECU may include a host processor that decides what the signals from the receiver and messages from stalk unit mean and what messages the ECU wants to send across the bus network, a controller (hardware and clock) in which incoming bits are stored before passing to the host processor and outgoing bits are stored prior to transmitting the bits serially onto the bus, and a transceiver that converts any incoming signals from the input nodes and output node into a form the controller can accept and vice versa.

Therefore the gateway controller unit may be configured to receive and to generate and transmit signals compatible with the CAN bus standard.

The memory may store samples of CAN signals (messages) from the main device with each signal associated with each user operable input means of the additional device and may associate each sample with a respective one S...

25 of the user operable input means. By storing the appropriate messages in the gateway controller unit to be sent whenever an associated input means of the additional device is operated, the network bus is provided with messages that can not be distinguished from messages from the main device, allowing it to be supplemented with the additional control.

The memory may be user programmable using a suitable installation tool, allowing each user input means of the additional input device to be assigned to a different CAN function message. As each vehicle may have unique CAN signals for each function, the additional device may learn these signals during an initial installation process.

The gateway controller unit may include at least one further input port which enables it to receive signals from at least one further additional user operable input device and receiver combination. An extra input device may be used as an alternative to the stalk which can be operated from a different position. In fact it is envisaged that one receiver may receive signals from more than one input device, so that a single receiver and input port can function with more than one input device. The memory may store messages to be associated with all the additional devices it is connected to.

Where additional input ports are provided, the gateway controller unit may modify signals from the main device, such as a stalk unit, according to the driver's intent as indicated by operation of the additional input devices at each input port.

The additional driver operable input device may comprise a keypad which may be secured to the steering wheel by a split connecting ring or jubilee 0*S* ::::. type connector or mounted via a bespoke method to the steering grip, such that the controls rotate when the steering rotates allowing them to be useable during steering manoeuvres.

The (optional) receiver and gateway controller unit may be combined within a single common housing. Alternatively they may be separate and *..: 30 connected through suitable electrical cable. When more than one additional input device is used such as a foot control in addition to a keypad, each may be provided with its own receiver. Alternatively a single receiver may handle all transmitted signals from each input device.

According to a second aspect the invention provides a method of modifying a vehicle of the kind in which a stalk control, or other main user operable control device, transmits operational messages to an ancillary device across a network bus, the method modifying the vehicle so as to include an additional user operable control device according to the first aspect of the invention which provides an alternative to the stalk control, or other main user operable control device, and which method comprises: fitting the supplemental operating device to the vehicle; and connecting the second port and third port of the gateway controller unit of the device to the vehicle bus.

The method may comprise fitting the additional user operable control device of the supplemental operating device to the steering wheel of the vehicle.

The method may preferably include steps of: identifying the connection from the stalk, or other control device, to the vehicle bus across which the stalk, or other control device, transmits its messages to the bus; *...

.. : severing the connection from the stalk, or other control device, to the S...

" 25 bus; and connecting the severed end connected to the stalk, or other control device, to the second input port of the additional operating device and the severed end connected to the rest of the vehicle bus to the output port.

.: 30 The method therefore connects a gateway ECU in between the stalk and the bus whilst severing the direct bus link from stalk to its associated ancillaries so all communication from stalk to bus has to pass through the gateway ECU where it may be modified, replaced or supplemented by messages generated by the gateway ECU.

The method may comprise severing the connection at the node of the bus to which the stalk control is connected such that only messages from the stalk are routed through the additional control device.

The method may comprise connecting two flying leads to the bus either side of a point at which it is to be severed, each lead connecting to a respective terminal of the second or third port and thereafter severing the bus between the connections to the flying leads.

The steps of the method need not be performed in the order that has been listed in the preceding paragraphs.

According to a third aspect the invention provides a vehicle that has been retrofitted with a device according to the first aspect and additionally or alternatively has been modified by the method of the second aspect of the invention.

The stalk or other user operable control device will typically connect to the bus at a node and the bus should be severed between the stalk and the * S S * node. *S..

**** 25 In one especially advantageous arrangement the additional operating device may be provided within a relay housing making it suitable for connection to a vehicle by plugging it into a free socket in a relay box fitted to the vehicle which has a connection to the vehicle bus.

The second and third ports may be connected to pins of the relay housing which fit into a socket in the relay box. It is this socket in the relay box that may be connected to the vehicle bus. In the case of a CAN bus, which carries information across twisted pair cables, only two connections from the bus to the pin receiving contacts in the socket need be made in some cases.

Therefore according to a fourth aspect the invention provides a relay box having at least one relay socket which has at least one pin receiving contact that is connected to a part of the vehicle bus such that the relay socket can receive an electronic control unit that either sends signals to or receives signals from the vehicle bus, or both sends and receives.

The control unit may be an additional control device in accordance with the first aspect of the invention.

Providing a modified relay box gives a convenient location within which to mount the additional control device. It also allows for existing vehicles to be easily modified to provide a convenient connection point for the device, since most current vehicles include relay boxes and often have spare sockets that could be made to communicate with the vehicle bus such as a CAN bus.

: The relay box may also include one or more fuse holders for receiving S...

.u 25 electrical fuses that link two contacts of an electrical circuit connecting the vehicle battery to a peripheral device such as lights, heater, door switches.

According to a fifth aspect the invention provides An installation tool for use in configuring a supplemental control device which is fitted to a vehicle to supplement a main control device that sends signals across a network bus, the supplemental control device being of the kind which comprises an additional user operable input device which includes at least one user operable input means which can be operated by the driver to select a function, the additional input device also including signal generating means for generating a signal responsive to operation of the input means, and a gateway controller unit mounted on the vehicle which includes a first input port for receiving the signal transmitted by the user operable input device and determines from the signal the function selected by the driver in operating the user operable input device, a second input port for receiving network bus messages from the main device which the additional control device supplements, and a third port through which the gateway controller unit may be connected to the network bus of the vehicle, and in which the installation tool comprises a first input port for receiving signals from the network bus of the vehicle prior to connection of the additional device to the vehicle network bus, a second input port for receiving signals from the additional device, prompt means to prompt an installer to operate a function on the main input device and to operate the corresponding user operable input means on the additional device which is to be assigned to that function, and an output port which enables the installation tool to pass signals to the gateway controller unit, the signals being generated by a configurating means which cause the installation tool to configure the additional device so that following connection of the .. : supplemental device to the vehicle operating the corresponding user S...

*"* 25 operable input means on the additional device causes a message to be applied to the network bus that would be produced by operating that function on the main device. S. * . * ..*

S

: 30 Providing the installation tool allows a generic additional device to be fitted to any CAN enabled vehicle to supplement the functionality of a main device which produces CAN signals because it enables the additional device to learn which CAN signals must be produced by each of its user operable input means to mimic the main device.

The prompt means may prompt the installer to operate in turn all of the functions on the main device and all corresponding inputs of the additional device, the configurating means configuring all of the inputs to give the correct signal to the CAN bus.

The tool may therefore ask the installer to operate all of the functions to be assigned to the additional control device in turn, and after all have been operated writes information to the additional control device which determines the assignment of functions to inputs of the additional control device.

The installation tool may comprise a processor and a display screen and the prompt means may comprise a computer program running on the processor which causes the display screen to display suitable prompts.

The installation tool may include an input port which enables signals from the main device and signals from the additional device to be received by the processor, and an output port through which configuration information can be passed from the processor to the additional device.

: The additional device may include an area of memory in which samples of "... 25 the signals sent to the network bus by each input of the main device are stored together with a table assigning each sample to the correct user operable input means of the additional device, the installation tool configuring the table during installation.

: 30 According to a sixth aspect the invention provides a method of identifying a signal associated with a device of a vehicle from a plurality of other

S

signals transmitted across a vehicle network bus, the method comprising the steps of: monitoring the network bus in a first period of time at which it is known or otherwise may be reasonably assumed that the signal to be identified is not being transmitted or is not changing and observing any signals transmitted on the bus in that period; causing the device on the network bus to be activated so that the signal to be identified is generated on the network bus in a second period of time different from the first period of time; monitoring signals sent on the network bus in the second period of time, and comparing any signals observed in the first period with signals observed in the second period, so as to identify the signal.

In the event that signals monitored in the second period are the same as the signals observed in the first period, the steps (b) to (d) may be repeated until a signal may be identified which differs, and may identify that as the signal.

In the event that more than one signal is identified in second period, the steps (b) to (d) may be repeated until only one signal differs and may idcntify that as the signal.

The step of comparing the signals and identifying the signal may involve a statistical analysis. * ** I. S

SSS S

The signals observed may comprise parts of a message.

The parts may be one or more bits of a byte of a message.

S ** 30 When the signal is not changing this can mean for instance that a part of a several bit message has not changed a value in the message to indicate a device has been activated. For example part of a message which is constantly being produced to indicate a device is inactive is not considered as changing. More than one part of a message may change at any instance and the comparison means may be arranged to detect which part of the message is responsible for indicating the device has been activated.

At least one characteristic of the identified signal may be recorded in a memory of a device to be connected to the bus.

The method may identify signals issued by user operable controls associated with auxiliary devices of the vehicle.

According to a seventh aspect the invention provides a computer readable medium which carries a computer program which when running on a suitable processor causes the processor to carry out the steps according to the sixth aspect of the invention.

According to an eighth aspect the invention provides a network bus analysing apparatus for use in identifying a signal from a plurality of other signals transmitted on a vehicle network bus, the apparatus : comprising: 25 a monitoring means arranged to monitor the network bus in a first period of time and a second period of time different to the first, and observe any signals transmitted on the bus in those periods, in the first period it is known or otherwise may be reasonably assumed that the signal to be identified is not being transmitted or is not changing, in the second period *: 30 of time the signal to be identified is generated on the network bus; an activating means arranged to cause the device on the network bus to be activated so that the signal is generated on the network bus in the second period of time; and a comparison mean arranged to compare any signals observed in the first period with signals observed in the second period, so as to identify the signal.

In the event that signals monitored in the second period are same as the signals observed in the fist, the activating means may cause the device to generate the signal on the network bus repeatedly until the signal may be identified.

In the event that the comparison means identifies more that one signal the activation means may cause the device to generate the signal on the network bus repeatedly until only one signal differs and may identify that as the required signal.

The comparison means may identify the signal through a statistical analysis.

The signals observed may comprise parts of a message.

The parts may be one or more bits of a byte of a message. * * ** *

* 25 At least one characteristic of the identified signal may be recorded in a memory of a device to be connected to the bus.

I ***

I

The apparatus may identify signals issued by user operable controls associated with auxiliary devices of the vehicle.

* I. 30 According to a ninth aspect the invention provides a method of fitting an additional user operable control device to a vehicle of the kind in which a stalk control, or other main user operable control device, transmits operational messages to an ancillary device across a network bus, the method modifying the vehicle so that the additional user operable control device provides an alternative input device to the main user operable control device; the method comprising the steps of: connecting a gateway controller comprising a first input port, a second input port and an output port to the network bus via the first input and output port, connecting the additional user operable control device to the second input port of the gateway controller, and configuring the additional user input device to operate the ancillary device by connecting an installation tool which programs the gateway controller to generate an operational signal of the kind produced by the main user operable control device when the gateway controller receives an input from the additional user operable control device.

The installation tool may program the gateway controller using the method according to the sixth aspect of the invention.

According to a tenth aspect the invention provides a method of configuring an additional user operable control device fitted to a vehicle of the kind in which a stalk control, or other main user operable control 0**S device, transmits operational messages to an ancillary device across a ** 25 network bus, the additional user operable control device being connected to the network bus through a gateway controller and provides an alternative input device to the main user operable control device; the method comprising the step of: monitoring the network bus in a first period of time at which it is known * * 30 or otherwise may be reasonably assumed that the signal to be identified is not being transmitted or is not changing and observing any signals transmitted on the bus in that period; causing the user operable control device on the network bus to be activated so that the signal to be identified is generated on the network bus in a second period of time different from the first period of time; monitoring signals sent on the network bus in the second period of time; comparing any signals observed in the first period with signals observed in the second period, so as to identify the signal; and configuring the gateway controller to generate the signal when the user operable control device is activated.

There will now be described, by way of example only, a number of embodiments of the present invention with reference to the accompanying drawings of which: Figure 1 is an overview of a part of a vehicle modified with an additional

control device in accordance with the prior art;

Figure 2 is a more detailed view of the electrical connection of part of the device of Figure 1 to the vehicle wiring loom; Figure 3 is an overview of a part of a vehicle modified with an embodiment of an additional control device according to the first aspect : of the invention; *....* 25 * ** Figure 4 is a schematic view of part of the electrical system of an unmodified vehicle which uses a CAN bus to connect a stalk unit to an S..

ancillary device; S. * S * S*S 30 Figure 5 is a schematic of view of that part of the electrical system of the unmodified vehicle shown in Figure 4 after it has been modified to include an embodiment of an additional control device according to the first aspect of the invention; Figure 6 is a schematic illustration of the key functional components of the additional control device used in the modification of Figures 4 and 5.

Figure 7 is an illustration of the connection of an installation tool to the additional control device for use during installation of the device; Figure 8 is a flowchart of the steps performed by the installation tool and an installer during an installation process; Figure 9 is an illustration of an alternative additional control device fitted to a vehicle; Figure 10(a) is an schematic representation of an embodiment of the apparatus according to the second aspect of the invention; and Figure 10(b) is an alternative embodiment of the apparatus according to the second aspect of the invention.

Figure 4 of the accompanying drawings shows schematically that part of a vehicle electrical system which connects a main user operable control *SS.

: device, such as a stalk input device, to a controlled device such as an 25 indicator for a vehicle prior to modification is shown. It comprises as its backbone a vehicle CAN bus network 100 of twisted pair cable which * electrically connects a number of nodes. Each node may be either an *0* * intermediate node at which there is a spur connection to one or more further nodes or a terminal node directly connected to a CAN ECU. Each ** 30 CAN ECU is associated with either a driver-operated control such as the stalk control unit ECU 106b for the stalk controls 106a on the left in Figure 4 or a peripheral electrical device such as the other nodes 110 on the right. Examples of controlled peripherals are headlight switches, indicator switches and windscreen wiper switches. This list is not to be considered exhaustive. The stalk may be moved to provide a simple on/off function such as lights on or off. In the unmodified vehicle shown in Figure 4, the CAN bus connection 100 carries messages from the column stalk node CAN ECU 106a to the other CAN nodes 110 in the vehicle. It may also carry messages from other vehicle nodes to the column stalk node.

The bus 100 comprises a loom of twisted pair wire that carries coded digital electronic signals between the stalk ECU and the devices at the other nodes.

Figure 6 shows an embodiment of a supplemental operating device which can be used in addition to or as an alternative input device to the stalk control unit 106 of the vehicle of Figure 4.

The supplemental operating device comprises a user operable input device 103 which includes at least one user operable input means which can be operated by the driver to select a function and which is secured to the steering wheel. This comprises a keypad 103a with a selection of buttons on a flat surface. Each button can be pressed to signal a driver's intent in the same way as the stalk can be operated. For example, a first button when pressed may indicate the same intent as moving a stalk upwards. A * second button when operated may indicate the same intent as moving that stalk downwards. A third button may indicate the same intent as S..

depressing the end of the stalk. S. * S * S..

*:*. 30 The input device of this embodiment also includes a wireless transmitter 103e and a processor 103b which includes a signal generating means for generating a signal responsive to operation of the buttons of the keypad which is transmitted by the transmitter 103e. When each button is pressed a signal is produced by the processor 103b within the device which runs operating instructions that are stored in a memory 103c associated with the device which causes the processor to generate or modify a signal that is passed to the transmitter. Of course a battery 103d may be provided as a source of electrical power for the processor and the transmitter.

The user operable input device 103, being wireless can be easily mounted in any convenient location. As shown in Figure 3 it is fixed next to a knob or handle 9 fixed to the steering wheel 4. It is located where the buttons can be pressed by a hand without having to release a grip on the handle 9.

The additional control device next includes a receiver device RX 107 mounted on the vehicle remote from the steering wheel 4 which receives the signal or signals transmitted by the transmitter TX 103e. In this example the transmitter and receiver transmit infrared signals 104 and so need to be mounted within line of sight of each other. In a modification the transmitter and receiver may send signals using omnidirectional radio waves (or some other form of omnidirectional transmission) and so do not need to be in line of sight. The receiver 106 may then be hidden away behind the dashboard of the vehicle or underneath the steering column. * *. ** *

*. 25 The output of the receiver 106, which is an electrical signal and most * * preferably a digital logic signal, is passed to a first input port 107 of a :.:. gateway controller unit 101. More specifically the output of the receiver S..

106 is fed to an input port of the gateway controller unit and passed to a uprocessor lOla. The controller unit 101 on receiving a signal at the first ** 30 input port determines from the signal the driver's intent by identifying which button and/or associated command is encoded in the message.

The gateway controller unit 101 functions as a CAN bus controller unit or node. It includes the first port for receiving signals from the receiver but also a second port 108 for receipt of signals output from a stalk fitted CAN ECU 106b to a vehicle. The controller 101 also includes a third port 109 which is suitable for connection of the controller unit to a network bus provided on the vehicle to which the stalk messages are required to be sent. As shown the connection comprises two pairs of twisted cable for connection to a CAN bus network.

In more detail the gateway controller 101 comprises a host processor lOla that decides what the signals from the stalk unit 106 mean and what messages the ECU wants to send across the bus network, a memory/buffer/controller in which incoming bits are stored before passing to the host processor and outgoing bits are stored prior to transmitting the bits serially onto the bus, and a transceiver that converts signals from the input nodes into a form the controller can accept and vice versa and a switching device lOib such as a relay that connects the two CAN buses together in the event of power failure or other detected error or failure.

: The additional control device may, of course, include other features. As 25 shown in Figure 6 for example one or more additional user operable input * ** devices may be provided. For example, these may duplicate functionality and allow that to be accessed from different locations on the vehicle.

* Alternatively they may provide for control of different devices. * S * *s.

Figures 3 and 5 illustrate the result of modifying a vehicle to incorporate the additional control device of Figure 6. A method of modifying the vehicle to provide the arrangement shown in Figures 4 and 5 will now be described.

To make the modification, all that is required it to break or sever the bus at point 105 between the stalk ECU 106b and the main backbone 100.

This is a simple act of cutting the twisted wires in the correct place. The vehicle CAN bus 100 is thereby broken at the spur 100 to the column stalk ECU. This will interrupt communications going to and from the column stalk ECU, but will not affect communications on the rest of the CAN bus. This will create two CAN buses, Column Stalk Can 102' and Vehicle CAN 100.

The two separate CAN buses 102', 100 formed by the split are connected to the second CAN input port 108 on the Gateway ECU 101 and the output port 109 respectively. The gateway ECU is capable of transferring data from the Vehicle CAN bus on to the Column Stalk CAN bus and vice-versa, i.e. transfer from the second port to the third port and vice versa. The gateway is therefore capable of transferring data as if the CAN buses were still connected together.

In use the gateway ECU controller 101 until will pass signals from its second port 108 to its third port 109 which are compatible with the CAN network. These may be signals from the stalk ECU CAN 106b or from the additional keypad, or modified signals from the stalk. Because a *. 25 break has been introduced into the CAN bus that is connected to the CS * ** node the CAN bus is diverted to the gateway ECU. There is then a CAN link from the gateway ECU to the column stalk node. This means that the gateway ECU is in complete control of the CAN communications between the column stalk and the rest of the vehicle CAN communications. The 30 ECU now becomes a sort of gateway between the column stalk node and the vehicle CAN bus, except that the ECU is able to control the transfer of information between these two communication buses and even inject new information into the transfer or modify existing information. It is the injection of information that is one of the advantages of the embodiment of the present invention.

When there are no key presses or column stalk presses, information may be passed between the vehicle bus and column stalk without modification.

Typically this may comprise simple dormant status messages. If the state of the column stalk switches is changed i.e. the driver uses the column stalk controls and not the keypad, then the state of the column stalk switches 106 will be transmitted from the column stalk controller ECU to the vehicle CAN bus without modification.

In the embodiment of Figures 3, 5 and 6 if the state of the keypad changes then the associated column stalk function is injected onto the CAN bus by superimposing it onto the column stalk control message coming from the column stalk unit. To other nodes this injection of information will look just like a normal column stalk control activation but in reality the column stalk controls have not been touched, only the steering wheel keypad.

The infrared communications can be replaced by a more generic wireless communication concept which should be faster and easier to package.

The wireless transmitter and receiver are embedded in the keypad and * 25 gateway ECU respectively. This also removes the concept of directional : * communications, where the previous infrared system has a potential weakness.

S

To operate a device otherwise controlled by the column stalk the driver *:*. 30 simply presses a key on the steering wheel keypad. This key-press is transmitted via the wireless link to the gateway ECU. The gateway ECU then injects this information into the column stalk CAN message.

In other words in the embodiment shown the gateway 101 is configured so that if there is no active control from either the Column Stalk Controls 106 or one of the Additional input devices 103 then the Gateway 101 will simply transfer any data from the Vehicle CAN bus and the Column Stalk CAN bus immediately and without altering any of the data.

If the Column Stalk Controls are operated by the driver then the Column Stalk ECU transmits this status over the CAN bus 100, as it would have before the modification. This status message is received by the Gateway ECU. The Gateway ECU simply repeats this message on the vehicle CAN bus without altering the contents of the message.

If the additional input device keypad is used, for example by pressing the first button on the keypad, then this new command is received or sensed by the Gateway ECU. The Gateway ECU will translate this control command into the equivalent command from the Column Stalk Control ECU, mimicking the column stalk control ECU function. Meanwhile, the Column Stalk ECU may be transmitting a periodic CAN message indicating that no driver control has been requested. The Gateway ECU will receive the Column Stalk Control message indicating no activity. It S...

: will then superimpose the Additional Control command over the original * 25 Column Stalk Control status message and transmit it over the vehicle * ,* CAN bus. To the rest of the nodes on the Vehicle CAN bus 100 it will look like the command has come from the Column Stalk ECU 106b, even though it has actually come from the additional input device. * . * I..

*** 30 This arrangement also allows for messages that need to be received by the Column Stalk Control ECU to keep it operating correctly. The communications provided by the Gateway ECU are bi-directional and non-discriminating, except for the Column stalk status message. This enhances this solution as it means that from the perspective of other CAN nodes on the vehicle there has been no change to the vehicle and likewise, ii also means that from the perspective of the Column Stalk ECU there has also been no change to the vehicle.

A feature of the Gateway ECU 101 illustrated in the drawings is its operation during failure. Fault detection mechanisms and power-off faults could potentially mean the loss of the Column Stalk function. A solution to this is for the CAN be re-connected from within the Gateway controller unit 101 through a normally open electrical connection becoming closed on operation of a relay or transistor switch during a fault, thus completely bypassing the Gateway ECU CAN nodes. The connection, which may simply comprises twisted wire pair and a switch lOib controlled by the processor are shown in Figure 6. This means that the Vehicle CAN and the Column Stalk CAN buses will be electrically connected to each other in the event of a failure of either the Gateway controller unit or associated additional input device. The effect of this is that the CAN bus 100 can be restored to its electrical status before modification with the Additional input device with the Gateway controller unit has been added. *...

: In an alternative arrangement it may be possible to connect the gateway S...

*** 25 ECU to the vehicle CAN bus through a suitably configured relay housing. * .*

Figure 7 is an illustration showing the connection of an optional configuration tool 70 to the additional control device that can be used to configure the additional control device during installation. The 30 configuration tool comprises a computer program running on a laptop computer which receives signals form the CAN and can write data to gateway ECU either via USB or CAN. If it proves that a laptop PC is not appropriate in some cases, then a smaller handheld option or even a larger rack mounted option could also be used.

The steps performed by the software once connected to the gateway ECU or CAN are illustrated in Figure 8 of the accompanying drawings. In a first step 80 the installer plugs the gateway ECU into the un-modified vehicle CAN bus. In the next step 82 the tool asks the operator to press a button on the additional secondary controller 103. The tool then asks installer to operate the equivalent column stalk control at step 84. The CAN signal this generates is identified and assigned to the button that the installer pressed, thus assigning that stalk function to the button selected by the installer. The tool checks/asks if all buttons have been configured in step 86. If not, steps 82 to 86 are repeated until all buttons have been configured. At the end of this process the CAN signal that is to be generated for each button press to provide the desired functions are written by the tool to the gateway ECU in step 88 and finally the tool can be removed and turned off at step 90.

The tool 70, when connected to the vehicle CAN or gateway controller will therefore ask the person performing the install to perform certain operations. From the operations the tool will intercept and analyse the CAN bus traffic and determine which CAN signals are associated with : which functions, and which buttons. From this information it will store a S... . . . **** 25 configuration in the gateway ECU that will then use the configuration to perform the conversion function during driving. The tool can then be removed.

Figure 9 is an illustration of an embodiment of an alternative ** 30 supplemental control device in accordance with an aspect of the invention. This embodiment operates in a manner similar to that of the first embodiment but differs in that the additional user control device is fitted to the vehicle body rather than to the wheel. It also differs in that the device additionally gives supplemental control over devices that are not associated with the Steering ECU. In this case it supplements the throttle/brake control signals that would be associated with an engine management and/OR brake ECU shown simply as ECU2 in Figure 8. The main user control device for throttle and brake would typically be foot operated so this supplemental device enables a driver to control the vehicle who would otherwise be unable to operate the foot controls.

As shown in Figure 9 the additional device may take the form of a joystick which can be moved forward/backward to control throttle and brake and which may also be moved side to side to generate other control signals. It may also, include at least one user operable button to control steering related functions such as indicators. Three buttons are shown in Figure 9.

Of course the tool may be used to identify signals from any device which operates on the vehicle network bus and those identified signals may be used to configure that device with an additional input device or any existing main control device. Alternatively, all that may be required is to identify a signal on the network bus from a particular device.

*:,:: Figure 10(a) of the accompanying drawings shows a schematic view of an *::::* 25 embodiment of the invention according to the second aspect. In this * ** example the vehicle network bus is a CAN bus system and the analysing apparatus 1002 is connected to the bus through a communication port ** * * 1007 so that signals sent on the bus can be received by the apparatus in the monitoring unit 1002. The monitoring unit passes signals sent on the network bus to a processor 1004 which communicates with a memory 1006 and a display 1005.

After attaching the apparatus to the CAN bus 1000 the processor 1004 provides an output on the display which instructs the operator of the apparatus through the identification procedure. Firstly the display instructs the operator to ensure the device with the signal to be identified is not activated so that either it is not transmitting a signal on the network bus or its signal is not changing. The operator can provide an input to the apparatus with button 1008 to indicate that the device is not activated.

Once this indication has been received, the processor then stores the signals sent on the CAN bus in the memory 1006 for a period of, for example, 30 seconds. At the end of this period the operator is then instructed on the display to start (by pressing button 1008) a second period of monitoring signals on the CAN bus in which the operator must activate the device so that a signal is sent or changed on the CAN bus which indicates that the device has been activated. The signals sent on the bus are again recorded in the memory 1006. The processor then compares the data in the two monitored periods to identify a new signal or a signal which has changed. If there is only one signal this will be identified on the display. In the event more than one signal is identified then the procedure is repeated to gather more information to assist in the signal identification. To further assist in the identification, the operator can be instructed to activate the device periodically or in a pattern which is known to the processor.

: An alternative embodiment of the invention according to the second 25 aspect is shown in Figure 10(b). In this example rather than an operator activating the device, there is a direct link between an activation unit 1009 which generates a signal causing the device to activate and produce an activation signal on the CAN bus and rather than outputting the device signal on the display an output port 1010 is provide so that a second 30 device such as an ancillary device to be controlled by the original device can be connected to the analysing apparatus 1002 and programmed to respond to the identified signal. * * * ** a ***. * a *.. * ** * S S a.. . a.. ** * S * **. S. * *.

Claims (40)

1. CLAIMS1. A method of identifying a signal associated with a device of a vehicle from a plurality of other signals transmitted across a vehicle network bus, the method comprising the steps of: (a) monitoring the network bus in a first period of time at which it is known or otherwise may be reasonably assumed that the signal to be identified is not being transmitted or is not changing and observing any signals transmitted on the bus in that period; (b) causing the device on the network bus to be activated so that the signal to be identified is generated on the network bus in a second period of time different from the first period of time; (c) monitoring signals sent on the network bus in the second period of time, and (d) comparing any signals observed in the first period with signals observed in the second period, so as to identify the signal.
2. 2. A method of identifying a signal according to claim 1 when in the event that signals monitored in the second period are the same as the signals observed in the first, the steps (b) to (d) are repeated until a signal is identified which differs, and identifying that as the signal.

   :
3. 3. A method of identifying a signal according to any preceding claim when in the event that more than one signal is identified in second period, the steps (b) to (d) are repeated until only one signal differs and * identifying that as the signal. I. *
4. 4. A method of identifying a signal according to any preceding claim *",j 30 in which the step of comparing the signals and identifying the signal involves a statistical analysis.
5. 5. A method of identifying a signal according to any preceding claim in which the signals observed comprise parts of a message.
6. 6. A method of identifying a signal according to claim 5 in which parts are one or more bits of a byte of a message.
7. 7. A method of identifying a signal according to any preceding claim in which at least one characteristic of the identified signal is recorded in a memory of a device to be connected to the bus.
8. 8. A method of identifying a signal according to any preceding claim in which the method identifies signals issued by user operable controls associated with auxiliary devices of the vehicle.
9. 9. A computer readable medium which carries a computer program which when running on a suitable processor causes the processor to carry out the steps of the method according to claims 1 to 8.
10. 10. A network bus analysing apparatus for use in identifying a signal from a plurality of other signals transmitted on a vehicle network bus, the apparatus comprising: a monitoring means arranged to monitor the network bus in a first period *..* : of time and a second period of time different to the first, and observe any S..., . 25 signals transmitted on the bus in those periods, in the first period it is known or otherwise may be reasonably assumed that the signal to be identified is not being transmitted or is not changing, in the second period S..of time the signal to be identified is generated on the network bus; an activating means arranged to cause the device on the network bus to be ** 30 activated so that the signal is generated on the network bus in the second period of time; and a comparison mean arranged to compare any signals observed in the first period with signals observed in the second period, so as to identify the signal.
11. 11. A network bus analysing apparatus according to claim 10 when in the event that signals monitored in the second period are same as the signals observed in the fist, the activating means causes the device to generate the signal on the network bus repeatedly until the signal is identified.
12. 12. A network bus analysing apparatus according to claims 10 and 11 when in the event that the comparison means identifies more that one signal the activation means causes the device to generate the signal on the network bus repeatedly until only one signal differs and identifying that as the required signal.
13. 13. A network bus analysing apparatus according to claims 10 to 12 in which the comparison means identifies the signal through a statistical analysis.
14. 14. A network bus analysing apparatus according to claims 10 to 13 in which the signals observed comprise parts of a message. *.S. :
15. 15. A network bus analysing apparatus according to claim 14 in which * ..

    * 25 parts are one or more bits of a byte of a message. * * ** *
16. 16. A network bus analysing apparatus according to claims 10 to 15 in which at least one characteristic of the identified signal is recorded in a memory of a device to be connected to the bus.

    *:*. 30
17. 17. A network bus analysing apparatus according to claims 10 to 16 in which the apparatus identifies signals issued by user operable controls associated with auxiliary devices of the vehicle.
18. 18. A method of fitting an additional user operable control device to a vehicle of the kind in which a stalk control, or other main user operable control device, transmits operational messages to an ancillary device across a network bus, the method modifying the vehicle so that the additional user operable control device provides an alternative input device to the main user operable control device; the method comprising the steps of: connecting a gateway controller comprising a first input port, a second input port and an output port to the network bus via the first input and output port, connecting the additional user operable control device to the second input port of the gateway controller, and configuring the additional user input device to operate the ancillary device by connecting an installation tool which programs the gateway controller to generate an operational signal of the kind produced by the main user operable control device when the gateway controller receives an input from the additional user operable control device.
19. 19. A method of fitting an additional user operable control device to a : vehicle according to claim 18 in which the installation tool programs the gateway controller using the method according to claims 1 to 8.

    *
20. 20. A method of configuring an additional user operable control device *** fitted to a vehicle of the kind in which a stalk control, or other main user operable control device, transmits operational messages to an ancillary device across a network bus, the additional user operable control device being connected to the network bus through a gateway controller and provides an alternative input device to the main user operable control device; the method comprising the step of: (a) monitoring the network bus in a first period of time at which it is known or otherwise may be reasonably assumed that the signal to be identified is not being transmitted or is not changing and observing any signals transmitted on the bus in that period; (b) causing the user operable control device on the network bus to be activated so that the signal to be identified is generated on the network bus in a second period of time different from the first period of time; (c) monitoring signals sent on the network bus in the second period of time; (d) comparing any signals observed in the first period with signals observed in the second period, so as to identify the signal; and (e) configuring the gateway controller to generate the signal when the user operable control device is activated.
21. 21. A supplemental operating device for use in modifying a vehicle which functions as an alternative device for operating one or more vehicle ancillary functions otherwise operated by at least one main user operable **.S : input device mounted on the vehicle of the kind which transmits messages S...for transmission across a network bus of a vehicle to which it is fitted, the supplemental device comprising: an additional user operable input device which includes at least one user operable input means which can be operated by the driver to select a function, the additional input device also including signal generating *:*. means for generating a signal responsive to operation of the input means; and a gateway controller unit which receives the signals from the user operable input means and determines from the signals the operation of the additional user operable input device, and in which said a gateway controller unit further includes a second input port for receiving a signal output from the main user operable device which the additional control device is an alternative to, and a third port through which the gateway controller unit may be connected to the network bus of the vehicle, the controller supplying bus messages to the network through the third port in response to operation of either the main device or additional device such that operation of the additional device causes the same messages to the transmitted through the third port as operation of a corresponding function on the main device.
22. 22. A supplemental operating device according to claim 21 in which the at least one main user operable input device comprises a column stalk unit.
23. 23. A supplemental operating device according to claim 21 or claim 22 in which the user operable input device comprises one or more keypads, footpads, or voice command units.
24. 24. A supplemental operating device according to claims 21 to 23 .. : which includes a transmitter and the gateway unit includes a receiver, the *...transmitter and receiver together enabling signals generated by the additional device to be sent wirelessly to the gateway unit.
25. 25. A supplemental operating device according to claim 24 in which the transmitter comprises a radio frequency transmitter and the receiver a radio frequency receiver responsive to radio waves transmitted by the transmitter.
26. 26. A supplemental operating device according to claims 21 to 25 in which the gateway controller unit is arranged so that any messages it receives from the main user operable input device are replaced by, modified by or supplemented with messages derived from the signals received at the first node.
27. 27. A supplemental operating device according to claims 21 to 26 which supplies at its third port signals compatible with a vehicle bus network which includes one or more of: messages it has received from a main user operable input device and which are unmodified; messages it has received from the main user operable input device which are modified by the gateway controller as a function of the signal received at the first port from the supplemental device; and new messages generated by the gateway controller unit from the signal received at the first input port which mimics messages from the main user operable input device.
28. 28. A supplemental operating device according to claims 21 to 27 which includes an electrical connection between the second input port and the output port which is normally open and which can be closed in the event that an error message is received by the additional control device at its output port and which when closed the additional control device is prevented from replacing or modifying signals from the main user operable input device and so disables functioning of the user operable * input device. S..S
29. 29. A supplemental operating device according to claim 28 in which *..: the direct connection is opened and closed by a relay.
30. 30. A supplemental operating device according to claims 21 to 29 in which the gateway controller unit includes at least one further input port which enables it to receive signals from at least one further additional user operable input device and receiver.
31. 31. A method of modifying a vehicle of the kind in which a stalk control, or other main user operable control device, transmits operational messages to an ancillary device across a network bus, the method modifying the vehicle so as to include an additional user operable control device according to the first aspect of the invention which provides an alternative to the stalk control, or other main user operable control device, and which method comprises: fitting the supplemental operating device to the vehicle; and connecting the second port and third port of the gateway controller unit of the device to the vehicle bus.
32. 32. A vehicle that has been retrofitted with a device according to any one of claims 21 to 30 and additionally or alternatively has been modified by the method of claim 31.
33. 33. A relay box having at least one relay socket which has at least one pin receiving contact that is connected to a part of the vehicle bus such . : that the relay socket can receive an electronic control unit that either S...sends signals to or receives signals from the vehicle bus, or both sends and receives. S..
34. 34. An installation tool for use in configuring a supplemental control device which is fitted to a vehicle to supplement a main control device ** that sends signals across a network bus, the supplemental control device being of the kind which comprises an additional user operable input device which includes at least one user operable input means which can be operated by the driver to select a function, the additional input device also including signal generating means for generating a signal responsive to operation of the input means, and a gateway controller unit mounted on the vehicle which includes a first input port for receiving the signal generated by the user operable input device and determines from the signal the function selected by the driver in operating the user operable input device, a second input port for receiving network bus messages from the main device which the additional control device supplements, and a third port through which the gateway controller unit may be connected to the network bus of the vehicle, and in which the installation tool comprises a first input port for receiving signals from the network bus of the vehicle prior to connection of the additional device to the vehicle network bus, a second input port for receiving signals from the additional device, prompt means to prompt an installer to operate a function on the main input device and to operate the corresponding user operable input means on the additional device which is to be assigned to that function, and an output port which enables the installation tool to pass signals to the gateway controller unit, the signals being generated by a configurating means which cause the installation tool to configure the additional device so that following connection of the supplemental device to the vehicle operating the corresponding user operable input means on the additional device causes a message to be applied to the network bus that would be produced by operating that function on the main device.

    * *. 25 * * S
35. 35. An installation tool according to claim 34 in which the prompt S..means prompts the installer to operate in turn all of the functions on the main device and all corresponding user operable input means of the *..: additional device, the configurating means configuring all of the inputs to by assigning the correct signal to each user operable input means so that it mimics operation of the corresponding function from the main device.
36. 36. An installation tool according to claim 34 or claim 35 which comprises a processor and a display screen and the prompt means comprises a computer program running on the processor which causes the display screen to display suitable prompts.
37. 37. An installation tool according to claims 34 to 36 which includes an area of memory in which a table is provided, the configuration means populating the table by storing messages associated with the input signals received from the additional device, the installation device transferring the populated table to the gateway controller to complete installation.
38. 38. A network bus analysing apparatus substantially as described herein, with reference to, and as illustrated in the accompanying drawings 10(a) and 10(b).
39. 39. An installation tool substantially as described herein, with reference to and as illustrated in the accompanying drawings 7 and 8.
40. 40. A supplemental operating device substantially as described herein, with reference to and as illustrated in the accompanying drawings 3, 5 and 6. * * * ** * *** S * . * ** * * S S.. * * **. S. * . * *.* S. * * . S