MXPA01003567A - A multimode i/o signaling circuit - Google Patents

Abstract

An I/O signaling circuit (250) having a single path through the circuit (250) which can be configured to operate in one of a plurality of modes. A first circuit (251) in the I/O signaling circuit adjusts the current flowing from a power supply to ground. A second circuit (252) adjusts the voltage between a positive potential terminal and negative potential terminal through a secondary processing device. A processor determines the proper mode in which the circuit is to operate and then generates signals to adjust the first and second circuits to configure the circuit.

Description

INPUT / OUTPUT SIGNAL CIRCUIT, MULTIMODAL FIELD OF THE INVENTION This invention relates to a circuit used to provide input / output signals between a first and a second device. More particularly, this invention relates to a circuit that can be configured to operate in one of multiple modes using a path through the circuit. Even more particularly, this invention relates to an input / output circuit in the electronic measuring equipment of a Coriolis mass flowmeter that minimizes the number of terminals required in the electronic measuring equipment to support different secondary devices They operate in different modes.

PROBLEM It is known to use Coriolis effect mass flowmeters to measure the mass flow and other information of materials flowing through a pipeline as described in U.S. Patent No. 4,491,025 issued to J.E. Smith, et. al., January 1, 1985 and Re. 31,450 of J.E. Smith of February 11, 1982. These flow meters have one or more flow tubes of a curved configuration. Each flow tube configuration Ref: 128116 in a Coriolis mass flowmeter has a set of natural vibration modes, which can be of a simple, torsional, radial or coupled type of bending. Each flow tube is driven to oscillate to a resonance in one of these natural modes. The natural vibration modes of the vibrating material filling systems are defined in part by the combined mass of the flow tubes and the material within the flow tubes. The material flows into the flow meter from a connected pipe on the input side of the flow meter. The material is then directed through the flow tube or flow tubes and out of the flow meter into a pipe connected to the outlet side. An actuator applies a force to the flow tube. The force causes the flow tube to oscillate. When there is no material flowing through the flowmeter, all points along a flow tube oscillate with an identical phase. As a material begins to flow through the flow tube, Coriolis accelerations cause each point along the flow tube have a different phase with respect to the other points along the flow tube. The phase on the inlet side of the flow tube causes the actuator to be delayed, while the phase on the output side directs the actuator. Sensors are placed at two different points in the flow tube to produce sinusoidal signals representative of the movement of the flow tube at the two points. A phase difference of the two signals received from the sensors is calculated in units of time. The phase difference between the two sensor signals is proportional to the mass flow rate of the material flowing through the flow tube or flow tubes. The mass flow rate of the material is determined by multiplying the phase difference by a flow calibration factor. This flow calibration factor is determined by material properties and properties of a cross section of the flow tube. Electronic measurement equipment that includes a processor and connected memory receives the sensor signals and executes instructions to determine the mass flow velocity and other properties of the material flowing through the tube. The electronic measuring equipment can also use the signals to monitor the properties of the Coriolis flowmeter components. The electronic measuring equipment can then transmit this information to a secondary processing device. It is also possible that the electronic measuring equipment receives signals from the secondary device for the purpose of modifying the operation of the flow meter. For purposes of the present analysis, a secondary processing device is any system capable of receiving signals from and / or transmitting signals to the electronic measurement equipment. The actual functions and operation of the secondary devices are not covered within the scope of this invention. It is a problem in the field of Coriolis flow measurement, in particular and in other fields in general, that different types of secondary processing devices can be connected to electronic equipment. Each different type of secondary processing device can communicate in one of several different ways. Some examples of different modes include, without limitation, digital signaling, analog signaling of 4-20 iliamperes, discrete, active signaling, discrete, passive signaling, active frequency signaling and passive frequency signaling. For each mode supported by the electronic measuring equipment or other electronic device in another field, the electronic equipment must have at least one terminal and typically two terminals connected to the circuitry necessary to support the mode. The need for separate circuits for each supporting mode by the electronic equipment is a problem. If the electronic equipment will be able to be adapted to provide signals in different modes to support different modes, an additional circuit must be added for each mode supported by the electronic equipment. Each additional circuit adds both the cost of the material and the cost of assembly to the electronic equipment. In addition, unless a specific circuit is added for a specific mode, the specific mode can not be supported by the electronic measurement equipment. There is a need in the technique of signaling input / output (I / O) in general and in the technique of Coriolis flowmeters, in particular, by a system that reduces the amount of circuitry in an I / O circuit while that minimizes the number of modes supported by the circuitry.

SOLUTION The above problem and other problems are solved and a breakthrough in the art is achieved by providing an input / output signaling circuit that is capable of operating in a plurality of modes insofar as it uses an individual route through the circuitry for transmitting signals to and / or receiving signals from a secondary device. This allows each input / output circuit in a device to operate in any of a plurality of modes that reduce the number of circuits necessary to provide input / output signaling between a first and a second device.

An input / output signaling circuit that is capable of operating in a plurality of modes while using an individual path through the circuit operates in the following manner. A power supply is connected to a positive output terminal. A variable impedance device, such as a transistor, is connected in the circuit between the positive terminal and a negative terminal. A second variable impedance device connects the negative terminal to a fixed resistor. The fixed resistor is then connected to ground. The first variable impedance device can be opened or closed to terminate a circuit between the positive and negative terminals within the input / output circuit in order to control the voltage between the positive and negative terminals. The second variable impedance device controls the current flow from the power supply to ground. The two variable impedance devices are controlled in the following manner to configure the I / O signaling circuit to operate in a particular mode. A controller executes instructions that determine the way in which signals are to be transmitted and generates signals that configure a circuit. The controller generates a first signal that is applied to the first variable impedance device. The first signal causes the first variable impedance device to terminate or disconnect a circuit which in turn controls the current flowing through the secondary device from the positive terminal to the negative terminal. In the preferred embodiment, the first signal is a digital signal that opens and closes a P-channel MOSFET transistor. A second signal is also generated by the controller, the second signal is applied to the second variable impedance. The second signal causes the second variable impedance device to change the amount of current flowing through the second variable impedance device on the ground. As the current flows to ground, the resistor connected to the second variable impedance device causes a voltage to be applied to an operational amplifier (Op-Amp) and made available to an analog converter a. digital (A / D). The Op-Amp also receives the second signal which is an analog signal. In Op-Amp it generates a control voltage which is then applied to the second variable impedance device to control the current flowing from the power supply to the resistor. The first and second signals are varied by the controller to transmit or receive signals in a desired mode as set forth below.

This invention is an integrated input / output signaling circuit capable of operating in one of a plurality of modes having a power receiving circuit that receives power, a high potential terminal that is connected to a load and a low terminal. potential (254) that is connected to the load. A first aspect of this invention is the configuration circuitry through the input / output signaling circuit that connects the power receiving circuit to the high potential terminal and the low potential terminal to provide a high terminal current to the terminal. potential and the low potential terminal on an individual path through the configuration circuitry where the configuration circuitry configures the individual path to provide current in one of the plurality of modes sensitive to the configuration circuitry that receives an input. A second aspect of this invention is that the configuration circuitry includes current flow control circuitry for controlling the current flow between the energy and ground reception circuit and the voltage control circuitry for controlling the voltage between the terminal high potential and low potential terminal.

Another aspect of this invention is that the current flow control circuitry includes a first resistor and a first transistor connected to the low potential terminal and an input of the first resistor. Another aspect of this invention is that the current flow control circuitry also includes a transducer near the input of the first resistor and an operational amplifier that receives an analog control signal from a processor and a voltage from the transducer and generates a voltage control that is applied to a gate of the first transistor that controls the current flow through the first transistor. Another aspect of this invention is that the current flow control circuitry also includes a first monitor path connected to the transducer. Another aspect of this invention is that the voltage control circuitry includes a second transistor connected between the high potential terminal and the low potential terminal that receives a digital input and establishes a circuit route between the high potential terminal and the terminal of low potential. Another aspect of this invention is that the voltage control circuitry also includes a first bias resistor connected between the energy receiving circuit and a gate of the second transistor for biasing the second transistor and a positive rail. Another aspect of this invention is that the voltage control circuitry also includes a second bias resistor that receives the input signal from a processor and has an output connected to the gate of the second transistor. Another aspect of this invention, wherein the second transistor is a source for draining the transistor and the power receiving circuit includes a fuse connected between an output of the second transistor and the low potential terminal. Another aspect of this invention is that the power receiving circuit includes a diode that prevents current from flowing to a low impedance power supply connected to the power receiving circuit when the power supply is cut off. Another aspect of this invention is that the plurality of modes includes an output mode of 4-20 milliamps. Another aspect of this invention is that the plurality of modes includes an input mode of 4-20 milliamperes.

Another aspect of this invention is that the plurality of modes includes a discrete, active mode of output. Another aspect of this invention is that the plurality of modes includes an output mode, discrete, passive. Another aspect of this invention is that the plurality of modes includes an active frequency output mode. Another aspect of this invention is that the plurality of modes includes a passive frequency output mode. Another aspect of this invention is that the plurality of modes includes a digital mode. Another aspect of this invention is that the plurality of modes includes an active discrete input mode. Another aspect of this invention is that the plurality of modes includes a discrete, passive input mode. Another aspect of this invention is that the plurality of modes includes a passive frequency input mode. Another aspect of this invention is that the plurality of modes includes an active frequency input mode. Another aspect of this invention is that the integrated input / output signaling circuit is incorporated into the electronic measuring equipment of a Coriolis mass flow meter. These and other advantages of the present invention will be apparent from the drawings and a reading of the detailed description thereof.

DESCRIPTION OF THE DRAWINGS Figure 1 is a common Coriolis flowmeter in the prior art. Figure 2 is a block diagram of the electronic measurement equipment in the. Coriolis flowmeter; Figure 3 is a diagram of an input / output signaling circuit of this invention; and Figure 4 is a flow diagram of the process of configuring the input / output signaling circuit to operate in a selected mode.

DETAILED DESCRIPTION Coriolis flow meter in general, Figure 1 Figure 1 illustrates a Coriolis flow meter 5 comprising a flowmeter assembly 10 and electronic measurement equipment 20. The electronic measurement equipment 20 is connected to the meter assembly 10 via conductors 100 to provide density information, mass flow rate, volume flow rate, total mass flow and other information on route 26. It should be evident for those skilled in the art that the present invention can be used by any type of Coriolis flowmeter despite the number of actuators or the number of transducer sensors. The flowmeter assembly 10 includes a pair of flanges 101 and 101 ', distributor 102 and flow tubes 103A and 103B. Connected to the flow tubes 103A and 103B is the actuator 104 and the transducer sensors 105 and 105 '. The reinforcing bars 106 and 106 'serve to define the axes W and W' around which each flow tube 103A and 103B oscillate. When the flow meter assembly 10 is inserted into a pipe system (not shown) carrying material to be measured, the material enters the flow meter assembly 10 through the flange 101, passes through the distributor 102 where the material is directed to enter the flow tubes 103A and 103B, it flows through the flow tubes 103A and 103B and back into the dispenser 102 where it exits the meter assembly 10 through the flange 101 '. The flow tubes 103A and 103B are appropriately selected and mounted to the distributor 102 to have substantially the same distribution of mass, moment of inertia, and elastic modules around the bending axes W-W and W-W ', respectively. The flow tubes extend outwardly from the distributor in an essentially parallel manner. The flow tubes 103A-B are driven by the actuator 104 in directions opposite their respective bending axes W and W 'and in what is called the first bending bend of the flow meter. The actuator 104 may comprise one of many well-known arrangements, such as a magnet mounted to the flow tube 103A and a composite spiral mounted to the flow tube 103B. An alternating current is passed through the opposite spiral to cause both tubes to oscillate. A suitable actuation signal is applied by the electronic measurement equipment 20, via the conductor 110 to the actuator 104. The description of Figure 1 is provided only as an example of the operation of a Coriolis flowmeter and is not intended to limit the teaching of the present invention. The electronic measurement equipment 20 receives the right and left speed signals that appear on the conductors 111 and 111 ', respectively. The electronic measurement device 20 produces the drive signal on the lead 110 which causes the actuator 104 to oscillate the flow tubes 103A and 103B. The present invention as described herein, can produce multiple drive signals from multiple actuators. The electronic measurement equipment 20 processes the left and right speed signals to compute the mass flow rate and provide the validation system of the present invention. Route 26 provides an input means and an output means that allows electronic measurement equipment 20 to be interconnected with an operator.

Electronic measuring equipment 20, in general.- Figure 2 Figure 2 illustrates a block diagram of the components of an example embodiment of electronic measuring equipment 20 carrying out the process related to the present invention. It is pointed out by those skilled in the art that the components of the electronic measurement equipment 20 shown are for the purposes of example only.It is possible to use other types of processors and electronic equipment in conjunction with the present invention. the various functions of the flowmeter including, without limitation, computing the mass flow velocity of a material, compute the volume flow rate of a material, and compute the density of a material from a single read memory (ROM) 220 via the route 221. The data as well as the instructions for performing the various functions are stored in Random Access Memory (RAM) 230. Processor 201 performs read and write operations on RAM 230 via route 231. Routes 111 and 111 'transmit the left and right speed signals from flowmeter assembly 10 to the equipment 20 electronic measurement. The speed signals are received by the analog-to-digital converter (A / D) 203 in the electronic measurement equipment 20. The A / D converter 203 converts the left and right speed signals to digital signals usable by the processor 201 and transmits the digital signals on the route 203 to the common bar 210 of input / output. The digital signals are transported by the common bar 210 of input / output to the processor 201. The actuator signals are transmitted on the common bar 210 of input / output to the route 212 which applies the signals to the analog-to-digital converter 202 (D /TO) . The analog signals of the D / A converter 202 are transmitted to the actuator 104 via the route 110. The route 26 carries signals to the secondary processing device 260 which allows the electronic measurement equipment 20 and the secondary processing device 260 to communicate with each other. . Route 26 includes routes 261 and 262 that are connected to terminal 253 of positive potential and terminal 254 of negative potential of signaling circuit 250 of input / output. The input / output signaling circuit 250 is a circuit that provides input / output signals in the electronic measurement equipment 20. One skilled in the art will recognize that the electronic measurement equipment 20 may have more than one input / output signaling circuit 250. However, only one I / O circuit 250 is shown for clarity purposes. Additionally, one skilled in the art will recognize that the functions and circuitry of the I / O signaling circuit 250 can be provided by any combination of circuits that can provide the functionality of the I / O signaling circuit 250. The I / O signaling circuit 250 receives and transmits signals to the common input / output bus 210 via the route 214. A person skilled in the art of electronic signaling will appreciate that the I / O signaling circuit 250 can be used. in other devices that require I / O signaling and is not limited to use in Coriolis electronic flow meter equipment. Route 214 includes a power supply route 240, a first data route 241, and a second data route 242. One skilled in the art will recognize that the first and second data paths 241 and 242 can be a plurality of lines in the common bus 214 that carry data to the circuit 250 or multiplexed signals on the same lines. The power supply path 240 is connected to the positive potential terminal 253 by the current flow control circuitry 251 and the voltage control circuitry 252 of the circuit 250. The negative potential terminal 254 is connected to the circuitry 251 of current flow and voltage control circuitry 252 to return the current flow from the secondary processing device 260 to the circuit 250. The current flow control circuit 251 is the circuitry that controls the current flow through of the circuit 250 of I / O signaling to ground. The input 241 is received by the current flow control circuitry 251 and causes the amount of the current flow to ground to adjust. The voltage control circuitry 252 receives the second input 242 and adjusts the voltage applied to the secondary processing device 260 in response to the received signal. The signaling circuit 250 I / O is different from other I / O circuits of the prior art since circuit 250 can be configured in the manner described below to provide I / O signals in one of multiple modes supported by a system with flowing current through circuit 250 on an individual route. This reduces the number of circuit routes through the I / O signaling circuit 250 which in turn reduces the number of components needed to manufacture the circuit 250. The configuration of the I / O signaling circuit 250 is performed by the processor 201 executing instructions to generate and transmit the appropriate signals to configure the I / O signaling circuit 250 for operation in the desired mode. The subsequent description of an example embodiment demonstrates how the I / O signal can be configured to perform in a specific mode using a route through circuit 250.

Circuit 250 of I / O signaling. - Figure 3 Figure 3 illustrates a preferred example embodiment of the I / O circuit 250. A person skilled in the art will recognize that there are other possible circuit configurations that can be used to obtain the same results. The I / O signaling circuit 250 receives power on the path 300 of a power supply. In this mode, the energy supply is a unipolar energy supply.

Route 300 passes through diode 301 which prevents current from flowing into the power supply when the power supply is stopped. Diode 301 is a conventional diode such as diode IN4001 produced by Motorola Corp. Route 300 is then connected to the terminal with the most positive potential, terminal 253 of positive potential. A second terminal is the most negative potential terminal and is called terminal 254 of negative potential. The positive potential terminal 253 and the negative potential terminal 254 are connected to the secondary processing device 260 to allow current to flow from the I / O signaling circuit 250 through the secondary processing device 260 and back to the secondary processing device 260. circuit 250. Those skilled in the art will recognize that it can also flow in the opposite direction. A first variable impedance device 310 is connected between the positive potential terminal 253 and the negative potential terminal 254 within the I / O circuit 250. In this exemplary embodiment, the first variable impedance device is a p-channel MOSFET transistor such as transistor 4P06 produced by Motorola Corp. The first variable impedance device 310 is connected to route 300 via route 309 and the element 312 of thermal protection via the route 311. The thermal protection element 312 protects the circuitry of the overcurrent as described below. The thermal protection element 312 is a self-resetting fuse such as part # SMD050 produced by Raychem. The output of the thermal protection element 312 is connected to the route 343. In this mode, the voltage control circuitry 252 is provided by the first variable impedance device 310. A digital signal is applied by the processor 201 via the route 330 to open and close the variable impedance device 310. Resistor 305 is connected between route 300 and 330. Route 330 flows through resistor 325. Resistors 305 and 325 polarize the variable impedance device of route 300. Resistors 305 and 325 are conventional resistors such as a film. metal of ten Kohm. It is possible to use many resistors of different strength in the present invention. Negative potential terminal 254 is also connected to comparator 340 via route 335. Comparator 350 senses the voltage level present at terminal 254 with respect to terminal 253. Route 335 passes through comparator 340 and transports signals to the I / O common bar 210 via route 391 and transmits it to processor 201. A second variable impedance device 345 is connected to route 335 returning from terminal 254 of negative potential. In this exemplary embodiment, the second variable impedance device 345 is an n-channel MOSFET transistor. The resistor 350 is connected between the second variable impedance device 345 via the improved mode 344 path and the ground. '"- The transducer path 355 provides the voltage across the resistor 350 to the Op-Amp 360. The transducer path 355 also provides the voltage through the resistor 350 to a monitor (not shown) The monitor (not shown) is an analog-to-digital converter that converts the received voltage over the route 355 into digital signals that can be read by the processor 201. The digital signals are then transmitted to the processor 201 via the common bus 210 of I / O. amp 360 receives an analog signal of processor control over the route 362 and the voltage across the resistor 350 over the route 355. The Op-amp 360 compares the received signal with the voltage of the resistor 350 and generates a control voltage that is applied to a second impedance device 345 via route 361. The control voltage controls the amount of current flowing through the second impedance device 345 to ground. The second variable impedance device 345 and the attached circuitry are the current flow control circuitry 251 of FIG. 2. The analog signal applied to the Op-Amp 360 is converted to a voltage that can be applied to the second device 345 of FIG. variable impedance. The first and second variable impedance devices 310 and 345 are then adjusted by the signals, from the processor to operate in a selected mode. The I / O signaling circuit 250 can be configured in the following modes by applying the following signals to the above described circuitry. The following examples are not intended to limit the functionality of the I / O circuit 250. It is left to those skilled in the art to program the processor 201 to operate in modes other than the example modes given below. A first mode in which the I / O signaling circuit 250 can be configured to provide is an analog output of 4-20 milli-amperes. In order to provide the output of 4-20 milli-amps, the processor 201 does not apply a signal to the first variable impedance device 310 which causes the first variable impedance device 310 to remain open. Processor 201 applies a variable, linear, scale voltage to Op-Amp 360 that creates a control voltage that is applied to the second variable impedance device that adjusts the current flowing from the power supply to ground. The strength of the signal is adjusted to encode the data in the current flowing through the secondary processing device 260. This allows the processor 201 to change the current flowing from the positive potential terminal 253 to the negative potential terminal 254 and through the secondary processing device 260. The secondary processing device 260 can then read the current that is applied to determine the data that is transmitted. The I / O signaling system can also be used as an input of 4-20 milli-amperes. To configure the circuit 250 to operate as a 4-20 milli-amp input, the processor 201 does not apply a signal to the first variable impedance device 310. The lack of a signal causes the first variable impedance device to remain open. The processor 250 applies a maximum, constant voltage signal to the Op-Amp 340 which causes a constant control voltage to be generated and applied to the second variable impedance device 345. This allows the flowing current to be limited by 250, but controlled by the secondary processing device 260. The processor 250 receives the current flow on the route 335 of the negative potential terminal 254 and the received current flow contains the data of the secondary processing device 260. Discrete data is a mechanism to indicate a digital state. A discrete value is one or zero in digital terms and is indicated by voltage across terminal 253 and 254 through secondary processing device 260. The I / O signaling circuit 250 can be used to encode discrete data. In order to provide a discrete, active input mode, the processor 201 applies a constant maximum voltage to Op-Amp 360 which in turn generates a constant control voltage over the second variable impedance device 345. The discrete value is then applied when affirming or de-asserting a signal to the first variable impedance device 310. The signal causes the first variable impedance device 310 to open and close which changes the voltage state between the positive potential terminal 253 to the negative potential terminal 254 presented to the secondary processing device 260. The voltage indicates the data that is transmitted. The I / O signaling circuit 250 'can also be configured to operate in a discrete input mode, active to receive data by applying a maximum voltage signal to Op-Amp 360 to generate a constant control voltage to the second device 345 of variable impedance. The data is then detected by the detected voltage on route 335 by comparator 340. In a discrete, passive output mode, processor 201 applies voltage 0 to Op-Amp 360 which generates a control voltage that prevents the current flow to earth. The data is encoded by asserting or declaring a signal applied to the first variable impedance device 310 to open or close the first variable impedance device 310. The I / O signaling circuit 250 can also be configured to operate in a discrete input mode, passive to receive data by the processor 201 by applying a signal of voltage 0 to Op-Amp 360 to generate a constant control voltage for the second device 345 of variable impedance. The data is then detected in the received stream on route 335 via Op-Amp 340. Also, the I / O signaling circuit 250 can be configured to operate in both active and passive frequency input and output modes. In a frequency mode, the data is an n-coded analog value. The processor 201 configures the I / O circuit 250 to operate in an active frequency output mode in the following manner. The processor 201 applies a maximum voltage to the second device 345 of variable impedance. In order to encode the data for the secondary processing device 260, the processor 201 applies a frequency signal to the first variable impedance device 310 which changes the voltage through the secondary processing device 260. The I / O signaling circuit 250 can also be configured to operate in an active frequency input mode to receive data by applying a maximum voltage signal to Op-Amp 360 -to produce a constant control voltage for the second device 345 of variable impedance. The data is then detected in the received stream on the route 335 through the comparator 340. The processor 201 can also configure the I / O circuit 250 to operate in a passive frequency output mode. The processor 201 applies a voltage signal 0 to the second 345 variable impedance device. In order to encode the data in the current applied to the secondary processing device 260, the processor 201 applies a frequency signal to the first variable impedance device 310. The I / O signaling circuit 250 can also be configured to operate in a passive frequency input mode to receive data by applying a voltage 0 signal to Op-Amp 360 to generate a constant control voltage for the second device 345 of variable impedance. The data is then routed to the received stream on route 335 via Op-Amp 340. The I / O signaling circuit 250 can also be configured to transmit and receive digital data. This digital protocol is the Bell 202 digital communication protocol. In order to configure the I / O signaling circuit to operate in the digital mode, the processor 201 does not apply a signal to the first variable impedance device 310 to prevent the first impedance device 310 terminates a circuit between terminal 253 of positive potential and terminal 254 of negative potential. A variable, linear, scale signal is applied to Op-Amp 345 with 1200Hz / 2200Hz data superimposed on the signal. The transmission data is received on route 335 through comparator 340.

Method to configure an I / O circuit. - Figure 4 Figure 4 illustrates the operational steps taken by the processor 201 in a process for configuring the I / O signaling circuit 250. Process 400 begins at step 401 by determining which mode supports the I / O signaling circuit 250. In step 402, the signals necessary to configure the circuit are applied to the I / O signaling circuit 250. In step 403, the processor 201 determines whether the mode to be supported is an input or output mode. If the mode to be supported is an input mode, the processor 201 reads the relevant signals from the I / O signaling circuit 250 in step 420. Step 420 is repeated until the mode of circuit 250 is changed to processor 201. If the signaling mode to be supported is an input mode, steps 410-412 are executed. In step 410, the processor 201 receives the data that is to be transferred. The data encoded in the signal is generated in step 411 and is applied to the I / O signaling circuit 250 in step 412. Steps 410-412 are repeated until circuit 250 is configured to operate in another mode. The foregoing is a description of an I / O signaling circuit having an individual path through the circuit that can be configured to operate in one of a plurality of modes. It is expected that those skilled in the art can design and design alternative I / O signaling circuits that contravene this invention as set forth in the subsequent claims either literally or through the doctrine of equivalents. It is noted that in relation to this date, the best method known by the applicant to carry out the present invention is that which is clear from the present description of the invention.

Claims (23)

1. CLAIMS Having described the invention as above, the content of the following claims is claimed as property: 1. An integrated input / output signaling circuit capable of operating in one of a plurality of modes characterized in that it has a power receiving circuit that receives energy, a high potential terminal that is connected to a load, a low potential terminal that is connected to a load, and configuration circuitry through the I / O signaling circuit that connects the energy reception circuit to the high potential terminal, and low potential terminal to provide a current to the high potential terminal and the low potential terminal on an individual route through the configuration circuitry wherein the configuration circuitry configures the simple route to provide current in one of the plurality of modes sensitive to the configuration circuitry that receives . an input, the configuration circuitry comprising: current flow control circuitry for controlling the current flow between the energy and ground reception circuit; and voltage control circuitry for controlling the voltage between the high potential terminal and the low potential terminal.
2. 2. The integrated I / O signaling circuit according to claim 1, characterized in that the current flow control circuitry comprises: a first resistor; and a first transistor connected to the low potential terminal and an input of the first resistor.
3. 3. The integrated I / O signaling circuit according to claim 2, characterized in that the current flow control circuitry further comprises: a transducer near the input of the first resistor; and an operational amplifier that receives an analog control signal and a transducer voltage and generates a control voltage that is applied to a gate of the first transistor that controls the current flow through the first transistor. I / O signaling according to claim 3, characterized in that the current flow control circuitry further comprises: a first monitor path connected to the transducer. The integrated I / O signaling circuit according to claim 1, characterized in that the voltage control circuitry comprises: a second transistor connected between the high potential terminal and the low potential terminal receiving a digital input and establishes a circuit route between the high potential terminal and the low potential terminal. The integrated I / O signaling circuit according to claim 5, characterized in that the voltage control circuit further comprises: a first bias resistor connected between the energy receiving circuitry and a gate of the second transistor for biasing the second transistor to a positive rail. ' The integrated I / O signaling circuit according to claim 6, characterized in that the voltage control circuitry further comprises: a second bias resistor that receives the input signal having an output connected to the gate of the second transistor. The integrated I / O signaling circuit according to claim 5, characterized in that the second transistor is a source for draining the transistor and the energy receiving circuitry further comprises: a fuse connected between an output of the second transistor and a high potential terminal. The circuit according to claim 1, characterized in that the energy receiving circuitry comprises: a diode that prevents current from flowing to a low impedance power supply connected to the energy receiving circuitry when the supply is stopped of energy. 10. The circuit according to claim 1, characterized in that the plurality of modes includes: an output mode of 4-20 milliamperes. The circuit according to claim 1 ', characterized in that the plurality of modes includes: an input mode of 4-20 milliamperes. The circuit according to claim 1, characterized in that the plurality of modes includes: a discrete, active mode of output. The circuit according to claim 1, characterized in that the plurality of modes includes: an output mode, discrete, passive. 14. The circuit according to claim 1, characterized in that the plurality of modes includes: an active frequency output mode. 15. The circuit according to claim 1, characterized in that the plurality of modes includes: a passive frequency output mode. 16. The circuit according to claim 1, characterized in that the plurality of modes includes: a digital mode. The circuit according to claim 1, characterized in that the plurality of modes includes: a discrete input mode, active. 18. The circuit 'according to claim 1, characterized in that the plurality of modes includes: a discrete, passive input mode. 19. The circuit according to claim 1, characterized in that the plurality of modes includes: a passive frequency input mode. 20. The circuit according to claim 1, characterized in that the plurality of modes includes: an active frequency input mode. 21. The circuit according to claim 1, characterized in that the integrated I / O signaling circuit is incorporated into the electronic measuring equipment of a Coriolis mass flow meter. 22. A method for configuring an integrated I / O signaling circuit to operate in one of a plurality of modes characterized in that it comprises the steps of: applying a first input to a first transistor connected between a high potential terminal and a low potential terminal to control the voltage between the high potential terminal and the low potential terminal; applying a second input to a gate of a second transistor connected between the low potential terminal and a grounded resistor connected to ground where the second transistor controls the current flow received from a power supply to ground; and apply sensible energy to the circuit that receives the first and second inputs. 23. The method according to claim 22, characterized in that it further comprises the steps of: determining which of a plurality of modes is to be provided by the integrated I / O circuit; generating a first input with a processor I responsive to a determination of one of the plurality of modes to be provided; generating a second input with a processor responsive to a determination of one of the plurality of modes to be provided; and transmitting the first input to the first transistor and the second input to the second transistor.