JPS5831219Y2 - Denso Souchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission device, and more particularly to a transmission device that can individually call each terminal device connected to the input side of a plurality of multiplexer circuits to a central processing control unit without multiple selection.

This type of device includes a central processing controller 1 as shown in FIG.
0 is equipped with an analog/digital converter 11, a digital computer 12, and a communication control device 13, and on the terminal side there is a multiplexer circuit 14 consisting of a register and a communication terminal that controls the multiplexer path under instructions from a central processing control unit. 15 remote terminal devices A, B...
is provided for each terminal, and the input side of the analog/digital converter 11 and the multiplexer circuit 1 of each terminal equipment.
The output side of 4 is connected to an analog bus 16, and the communication control device and the communication terminal of each terminal device are connected to each other by a digital bus 17. The communication terminal of the called terminal device drives the register for holding the channel switch, closes the analog switch of the specified channel, and transmits the analog information of that channel via the analog bus. Supplies the input side of the analog/digital converter of the central processing unit.

However, in such a transmission device, since the output of the multiplexer circuit of each terminal device is connected to an analog bus for data transmission, it is necessary to call each terminal device individually.

That is, after converting the information of a certain terminal device by an analog/digital converter during data transmission, the multiplexer circuit of that terminal device must be turned off before selecting the multiplexer of the next terminal device, otherwise errors due to multiple selection will occur.

In order to reliably prevent such multiple selection, a command is issued from the central processing unit to reset the multiplexer of the terminal device that has undergone analog/digital conversion.

If a reset command is required in this way, data transmission becomes complicated, and it takes longer to transmit one data except for the reset signal, which has the disadvantage that the system data transmission time becomes longer.

The purpose of the present invention is to provide a transmission system that does not generate multiple selection errors without applying a reset signal to the multiplexer circuit when an analog-to-digital converter that converts an analog input signal into a digital quantity completes the conversion operation. The goal is to provide equipment.

An overview of how to achieve this purpose is that data transmission between the central processing control unit and each terminal device is generally carried out using specific keywords, and with this in mind,
Even without issuing a reset command, the multiplexer circuit is automatically reset if the address of the terminal device for channel selection changes.

That is, for example, it is composed of a binary 8-pit code, and the pit information corresponding to the first to third digits constitutes the terminal address number, and the pit information corresponding to the fourth and fifth digits constitutes the terminal equipment. Key Index of Circuit Selection, Section 6.7.
If a keyword is transmitted to each terminal device, with the pit information corresponding to the 8th digit as the channel, a keyword translation circuit is installed in each terminal device, and the key index is focused on. A signal for setting or resetting the multiplexer circuit is generated based on the presence or absence of multiplexer circuit selection information, and the multiplexer circuit is controlled by the cent/reset signal.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings, with the same numbers assigned to circuits having the same functions as those in FIG. 1, and their explanations omitted.

The difference is in the remote terminal equipment, which includes a communication terminal 15, an address decoder 18 and an index decoder 19 that decode the address part and index part of the keyword output from the communication terminal, respectively, and an address decoder. A first AND circuit 20 that ANDs the outputs of the hexagram and index decoder and outputs a set signal when the result is true, and a first AND circuit 20 that takes the AND of the output of the address decoder and the output of the index decoder and outputs a reset signal when the result is true. The second output
Consists of an AND circuit 21 and a multiplexer circuit 14 that connects the output side to the analog bus, closes the channel switch corresponding to the channel signal, and opens the output side from the analog bus when a set signal is applied. .

To explain the operation of the terminal device configured in this way, a control signal from the digital computer 120 is received by the communication control section 13 via the digital bus 17 at the communication terminal of each remote terminal device.

By the way, in the remote terminal device called by the control signal, the keyword signal is decoded by the address decoder 18 and the index decoder 19, and when the index decoder detects its own key index, if the content of the address decoder is related to the self, the multiplexer circuit is activated. Set, if not on self, causes the multiplexer circuit to be reset.

When set, the multiplexer circuit selectively activates each analog switch based on the keyword channel signal, and the signal of each channel is routed through the selectively activated analog switch and multiplexer switch via the analog bus. Analog/digital converter 1
1.

As is clear from this, the multiplexer circuit of the terminal equipment that matches the keyword index signal is set when the address of the terminal equipment matches, and is reset when there is a mismatch.

That is, if the terminal device is changed, there is no need for the digital computer to give a reset command to the multiplexer circuit.

The invention described in detail above is based on a keyword in a digital computer, and is configured to control the multiplexer circuit of a terminal device from the address field and index of the keyword, so if the address changes, the multiplexer circuit is selected and activated. Since the multiplexer circuit is automatically reset, there is no need for the digital computer to give a reset signal to reset the multiplexer circuit, and the system transmission time can be shortened while allowing the transmission from the selected terminal to the next terminal device. This has the effect of eliminating errors caused by multiple selection at the point of change.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a conventional transmission device.
FIG. 2 is a block diagram showing the configuration of remote terminal equipment in the transmission apparatus according to the present invention. 11... Analog/digital converter, 12... Digital computer, 13... Communication control device, 14...
Multiplexer circuit, 15... Communication terminal, 18...
Address decoder, 19... index decoder,
20.21...AND circuit.

Claims (1)

[Scope of utility model registration request] Central processing and control unit analog bus and digital bus
The bus is connected to each of multiple remote terminal devices, and the remote terminal number, the selection signal of the circuit configuring the terminal device, and the analog input channel signal are sent to the digital bus to select the input channel of the multiplexer of the corresponding remote terminal device. In those connected to an analog bus, the remote terminal equipment includes a multiplexer consisting of a plurality of analog switches coupling the output side to the analog bus and a register for selectively driving the analog switches, and an input side connected to the digital bus. a communication terminal that outputs a remote terminal number signal, a selection signal for a circuit configuring the terminal equipment, and an analog input channel signal, an address decoder that generates a signal when the remote terminal number signal is self, and a register of a multiplexer whose circuit selection signal is an index decoder that generates a signal when the output of the address decoder and the output of the index decoder are satisfied; A transmission device comprising a second AND circuit that resets the register when an AND is established.