JPS6016995Y2 - Data bus transfer mode switching control device - Google Patents

Description

[Detailed Description of the Invention] The present invention is directed to a data bus transfer mode switching control device, in particular a data bus transfer mode switching control device, which is used to transfer data between a central processing unit and a channel.
Status information for displaying lamps is always selectively transmitted on the bus, and data is transferred instead of the above status information only when the need for data transfer arises. The present invention relates to a data bus transfer mode switching control device that improves bus usage efficiency and saves mounting space by omitting a status information bus.

A data bus is provided between the central processing unit and the channels, and data is sent and received via the data bus based on an interface using control signal lines.

However, if the data bus has a bus width of 1 byte and a maximum of 4 bytes of data is transferred, the data bus is occupied for the 4 bytes of data transfer. The time is a relatively short time (for example, about 1 μs), whereas it is a relatively long time (for example, about 1 μs).
For example, when data transfer is repeated every several tens of microseconds, the usage efficiency of the data bus is extremely low.

On the other hand, a status information bus is provided in order to display the status information of the channel by a lamp on the central processing unit side, but in the case of the lamp display, there is almost no problem even if there is a turn-off period of about 1 μS.

When data is sent and received via the data bus, there is a predetermined interface procedure between the central processing unit and the channel, and the central processing unit and the channel each know the data transfer period. be able to.

Focusing on the above points, the present invention eliminates the status information bus that overcomes the bit width restriction of the information to be transferred, and allows the data to be transferred selectively at all times via the data bus. It is an object of the present invention to provide a data bus transfer mode switching control device that switches a data bus to a data transfer mode when the need for transfer arises.

Therefore, the data bus transfer mode switching control device of the present invention includes a central processing unit and one or more channels connected to the central processing unit, and has a central processing unit and one channel connected to the central processing unit. Data is transferred via a data bus based on a predetermined interface, and status information within the channel is supplied to the lamp between the central processing unit and the channel, and notification is provided by the lamp display. In the data processing device, the central processing unit sends a status information selection signal to the one or more channels, and selectively transmits the status information selected by the selection signal via the data bus. is configured to receive data and display a lamp, and to interpret the interface, switch modes, and transmit the data during a period when data is transferred based on the interface between the central processing unit and the channel. - configured to turn off the route by which information on the bus is supplied to the lamp, such that the central processing unit and the channel are configured to A central processing unit selectively receives and supplies status information for displaying the lamps, and is configured to turn off the route during periods when data is being transferred via the data bus. It is characterized by

This will be explained below with reference to the drawings.

The figure shows the configuration of an embodiment of the present invention.

In the figure, reference numeral 1 is a central processing unit, 2-0. 0.8-1
are data buses, 9-0. 9-1 each represent a control signal line.

When it is assumed that 64 bits of status information is received from one channel and displayed on a lamp, there is a selection switch in the central processing unit 1 that selects a 3-bit selection signal, and the 8 bits obtained by the selection switch are The selection signals for channels 2-0, 2-1 . ... (may also be transmitted using data bus 8-0.8-1).

On each channel side, 1 byte (8 bits) of status information corresponding to the selection signal is transmitted via the transmitting/receiving section 3 onto the data bus 8-0.8-1! On the central processing unit 1 side, the above-mentioned status information is displayed on the receiving section lamp display section 7 via the receiving section 4.

When the central processing unit 1 changes the selection signal, another 1-byte status information is transmitted from each channel 2-0, 2-1, . . . and displayed by a lamp.

For example, when it becomes necessary to transfer data between the central processing unit 1 and the channel 2-0, the data transfer is performed between the two based on a predetermined interface.

That is, for example, based on a data transfer request from channel 2-0, central processing unit 1 sends a service-in signal to control line 9-0, and based on this, channel 2-0 sends a service-in signal to mode switching signal generator 5. The mode is switched by , and the data is sent out onto the data bus 8-0 via the transmitter/receiver section 3.

At this time, central processing unit 1 knows that data will be transferred from channel 2-0, and only during this period, mode switching signal generator 6 transfers data from channel 2-0 onto data bus 8-0. Prevents the signal from being transferred to the lamp display section 7.

The data on the data bus 8-0 is then electrically transmitted to a data transmitting/receiving section (not shown).

Needless to say, when transmitting data from the central processing unit 1, the central processing unit 1 transmits a service out signal to the control line 9-0. Switch.

As stated at the beginning of this specification, the data transfer between the central processing unit 1 and each channel 2 is, for example, several dozen
This is carried out with a period of μs and takes at most 800 pn.

Therefore, the usage efficiency of the data bus is about 1150.

In the case of the present invention, as described above, the idle period of the data bus is used for transmitting status information for displaying lamps, etc., and the conventional status information bus can be omitted.

In the case of a lamp display, even if the lamp is turned off for about 800 ns, there is no inconvenience, and the operator observes it as being continuously lit.

As explained above, according to the present invention, the bit widths of the status information and the data to be transferred are different;
Also, it has become possible to solve the problem that the lamp display may become undesirable during data transfer with a simple configuration.

[Brief explanation of drawings]

The figure shows the configuration of an embodiment of the present invention. In the figure, reference numeral 1 represents a central processing unit, 2-0, 2-1 are channels, 3 is a transmitting/receiving section, 4 is a receiving section, 5 and 6 are each a mode switching signal generating section, and 7 is a lamp display section.

Claims (1)

[Scope of utility model registration request] A central processing unit and one or more channels connected to the central processing unit are provided, and data is transferred between the central processing unit and the one channel via a data bus based on a predetermined interface. In the data processing device, the central processing unit and the channel supply status information in the channel to a lamp and provide notification by displaying the lamp. The device is configured to transmit a status information selection signal to the channel of the controller, selectively receive the status information selected by the selection signal via the data bus, and display the status information with a lamp. Interpreting the interface during data transfer based on the interface between the processing unit and the channel, switching the mode, and turning off the route by which the information on the data bus is supplied to the lamp. The central processing unit is configured to selectively display status information for displaying the lamp during a period other than when data is being transferred between the central processing unit and the channel via the data bus. A data bus transfer mode switching control device, wherein the data bus transfer mode switching control device receives and supplies the data to the lamp, and is configured to turn off the route during a period when data is being transferred via the data bus.