JPS5928674A - Disconnecting detection of transmission wire - Google Patents

Abstract

PURPOSE:To enable the indication of the interruption in a processing operation or the like owing to wrong read data, by detecting the failure in inversion of N- pieces of transmission wires simultaneously to a logical level ''H'' for a specified time or above on a reception side and deciding the generation of a disconnection. CONSTITUTION:When an AND gate 3 detects a coincidence, a retriggerable monostable multivibrator 4 is triggered at each detection. The normal time T of the vibrator 4 is set at T>t1+t2; therefore, if transmission wires l1-l4 are normal, the vibrator is retriggered within the time T and the output Q of the vibrator 4 is maintained at an ''H'' level, but when at least one among the wires l1-l4 is disconnected, the vibrator 4 fails to be retriggered in the time T and therefore the output Q is reset to a logical level ''L''. The generation of an interruption pulse P2 is indicated by a pulse generator 5 at the negative edge where the Q output of the vibrator is reset to the level ''L''.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission line disconnection detection method, and an object thereof is to provide a method that can quickly detect a transmission line disconnection when data is repeatedly transmitted via the transmission line. .

The data transmission/reception method since ση is shown below. This first
1 is a transmission side (
Connect 1u and receive ll1lI (RX), and send 1u
ll (TX) c is 4-bit digit series name data D
, DLI... are sequentially applied in bit parallel to the transmission lines j, ~14 as shown in FIG. ) is applied to the strobe signal line 15VC. On the receiving side (RX), each time the strobe signal line 15vC strobe signal P is generated, the state of the four transmission lines 1 to 14 at that time is read as data. However, in the past, a disconnection check for transmission #11 to #14 was not performed during data transmission, and if the disconnection occurred, the receiving side (RX) would read incorrect data. Currently, it is not possible to interrupt processing due to this incorrect data.

Therefore, in the present invention C1, all pits are simultaneously processed at the processing level WH'.
11 bits ■ N transmission lines that transmit data sequentially are transmitted on the transmitting side between the data transmission path time r and the next data transmission start time every time one data transmission ends. All logic levels 1H1 for at least a predetermined period of time
However, the reception 11111 detects that the N transmission lines do not switch to the cooking level 1H'' at the same time for more than -1 hours and determines that a disconnection has occurred. An example of this is shown in Figures 3 and 4.
:I will explain about 4. Note that an example in which data is transmitted from an electronic toll scale to a printer device will be described here.

(1) Stepchild charge scale as l-j sending side, (2) printer cylinder as receiver side, /1 to 14 are electronic charge scales 4 connecting the sword/su (1) and printer device (2). It is a wooden transmission line. The electronic toll scale (1) side has data to be transmitted such as tare, weight, both ways, 'f-llll1+, etc. The data sending routine is configured as follows.

In the microcomputer (A), it is determined that the order of data to be transmitted is a repeating cycle 'C' in the order of tare → hydrochloric acid → price → unit price as shown in Figure 4 (a). The time t2 between the transmission path r time and the start of the next data transmission is F16 [If written in bits, transmission M/, ~
All 14 data are held at the processing level l HI [state] and transmitted. It is composed of L. Note that the data is transmitted in bit parallel and digit series, respectively.
Each data transmission time t1 is equal, and the time t2 until the next data is also equal. Also, microcomputer (A)
In synchronization with the transmission of each data, a 710-bit signal P1 is generated on the strobe signal line 15 as shown in FIG. 4(b) as in the conventional case.

Glinter equipment that reads the upper 1 pin data via the transmission line /,~14! (2) (According to the regulations, a microcomputer (B
) is read each time as data of the states of the transmission lines 11 to 14 at the timing when the strobe signal line 15vC strobe signal P is generated. In addition, a printer device (
On the 2) side, QJ1 and gate (3) connects transmission lines 11 to 14.
When σ) ant game 1-(3J detects a match as shown in FIG. Trigger as shown in figure (d).Here, the standard time T of the monostable-furte vibrator (4) is T ) t , 0t
, , so that if the transmission lines 11 to 14 are normal, the output Q of the monostable multibiflator (4) is maintained at 1H level by re-triggering σi within the time T. However, if at least one of the transmission lines /1 to /14 is disconnected, the monostable multibar f flake (4) will not be triggered within the specified time T, so the output Q will return to the logic level WL1. At the negative edge when the output Q of the monostable multivibrator (4) returns to the logic level I L l, the pulse generator (5) is instructed to generate an interrupt pulse P2.This interrupt pulse P2 is generated by the microcomputer CB). acts as an interrupt signal on the microcomputer (f31
5. The strobe 1d is configured to suspend the reading operation of the 7+η irises due to P and V, and execute the routine of 10. disconnection notification. In addition, the disconnection notification routine 7 and Q', which indicates, for example, transmission line disconnection, can be printed out.In the example, the entire area during 61 hours t2 over 1
6, this is C during time t2.
, it is only necessary that the animation number 3) is longer than the time required to read the data.

As described above, according to the present invention, when at least one transmission line is disconnected, this disconnection state can be promptly detected and an instruction can be given to interrupt processing operations due to incorrectly read data.

[Brief explanation of the drawing]

Figure 1 is a connection diagram of the conventional data transmission/reception (i-method sending and receiving sides), Figure 2 is a waveform diagram of Figure 1, and Figure 3 is the present invention +7.
) J4. Configuration diagram of an embodiment inside the body, Fig. 4(a) to (d)
, ) is the transmission format shown in FIG. 3 and the main waveform diagram C inside the receiving side. (1)...Electronic toll scale [sending side], (2J...
Printer device [receiving side], (3)...Anotogame),
(4)... Gakken multi-buy break, (5)...
Pulse generator, (A) (b)... Microcontroller, /1 to E4... Transmission line, 15... Strono signal green, P2... Interrupt pulse agent Morimoto
Yoshihiro

Claims (1)

[Claims] ] - All pits are not inverted to logic level 1H1 at the same timeN
N-tree transmission lines that transmit bit data sequentially are set to a logic level for at least a predetermined period of time on the transmitting side, every time one data transmission ends, from the data transmission end time to the next data transmission start time. @H@vc A transmission line disconnection detection method in which the reception side detects that the N transmission lines do not simultaneously invert to the logic level IH' over a certain period of time and determines that a disconnection has occurred.