JPS6116108B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multiple processing method for edge signals in a signal line for detecting changes in the state of various factors.

Generally, in an office computer, etc., the central processing unit is notified of changes in status due to various factors, and the central processing unit receives the notification and uses a factor sense to detect which factor caused the change. Measures have been taken to carry out signal processing.

Conventionally, dedicated drive lines have been used as signal lines for notifying the central processing unit of changes in status due to various factors, resulting in a large number of lines.

The present invention is capable of reliably notifying a central processing unit, etc. of changes in the state of each factor through a common signal line, without providing a signal (edge signal) line for each factor to notify the change in its state. The present invention provides an edge signal multiplexing method that enables edge signal processing.

When notifying the upper central processing unit of changes in the status of various factors via a common signal line, if multiple factors conflict and drive the shared line, the edge signal of the factor driven later changes. There is a strong possibility that the information will disappear and it will no longer be possible to notify changes in the status.

Therefore, in the edge signal multiple processing method according to the present invention, the change in state is held for each factor, and after the central processing unit senses the factor in response to the edge signal, the held state is reset, and in response to the reset, the change in the state is held. By taking measures to temporarily deactivate the shared line, even if multiple factors conflict with each other to drive the shared line, the edge signal of the latent cause that was later driven when the shared line is restored to active state. We are trying to make it possible to cause this.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an example of a configuration for concretely implementing the edge signal multiplexing method according to the present invention. Factor holding circuits 2, 3, and 4 to be held, and a reset signal that resets each of the factor holding circuits 2, 3, and 4.
A delay circuit 6 that delays RESET and activates a disable terminal of a driver (activation controller) 5 provided on the shared line 1 using the delayed reset signal to temporarily deactivate the shared line 1. It is structured accordingly.

In the device configured in this way, a change in state has now occurred in the factor A, and the factor holding circuit 2 is set, and the set output drives the shared line 1 to the central processing unit (not shown). When a change in status is notified, the side receiving the notification executes factor sensing to detect which factor caused the change in status. At this time, if a state change of factor B occurs during the sensing of factor A and the factor holding circuit 3 is set and driving the shared line 1, then the factor A changes when the factor A is sensed.
and factor B are detected to be driving the shared line. A reset signal issued from the central processing unit, etc. when factors A and B are determined.
Each of the factor holding circuits 2 and 3 is reset by RESET, but in the meantime, when the state of factor C changes and the factor holding circuit 4 is set, and the shared line 1 is driven, factors A and B are reset. At the time when it is set, the edge signal on the shared line 1 no longer changes because the driving by the factor C continues. Therefore, in this invention, especially in such a case, factors A and B are
The reset signal RESET (which has a fixed time interval to ensure reset of the factor holding circuits 2 to 4) issued after sensing is delayed for a predetermined time by the delay circuit 6, and the delayed reset signal is is applied to the disable terminal of the driver 5 to temporarily deactivate the shared line 1, thereby returning the shared line 1 to the state before it was driven, and after the activation of the shared line 1 is restored, the factor is maintained. The shared line 1 is driven again by the set output of the circuit 4. Therefore, the edge signal of the factor C driven later can be obtained on the shared line 1, thereby making it possible to reliably notify the central processing unit or the like of a change in the state of the factor C.

In addition, FIG. 2 shows the state changes of each factor A, B, and C in the case of the embodiment described above, the factor sense,
The timings of the reset of each of the factor holding circuits 2 to 4 and the edge signal on the shared line 1 are shown, respectively.

As described above, in the edge signal multiplexing method according to the present invention, changes in the state are held for each of a plurality of factors connected to the edge sense common line,
This system uses a means to reset the held state after sensing the factor, and a means to temporarily deactivate the shared line in response to the reset, so that it can be used even if multiple factors conflict with each other to drive the shared line. Even if the shared line is restored to active state, it is possible to generate edge signals of latent factors that were driven later, and the state change of each factor can be detected by the central processing unit at the time when the shared line drive conflict occurs. It has the excellent advantage of being able to reliably inform the public.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a configuration for concretely implementing the edge signal multiplexing method according to the present invention, and FIG. 2 is a time chart showing an example of the timing of the operation of each part in the same embodiment. 1... Shared line, 2, 3, 4... Factor holding circuit, 5... Driver, 6... Delay circuit.

Claims (1)

[Claims] 1. Means for retaining changes in the state of each of a plurality of factors connected to an edge sense shared line, and resetting the retained state after sensing the factor, and means for temporarily inactivating the shared line in response to the reset. This edge signal multiplexing method generates an edge signal of a latent factor when the shared line is restored to active state when multiple factors compete to drive the shared line.