JPS58169613A - Data transfer method - Google Patents

Abstract

PURPOSE:To realize the continuous transfer of data having high priorities, by delivering continuously the bus occupation request signals through channels of high priorities and meanwhile inhibiting the occupation request signals supplied through channels of low priorities. CONSTITUTION:Plural channels 3A-3D are connected succesively in accordance with the priorities to remote terminals at a bus control part 2. The channels 3A-3D have bus occupation request control circuits 5A-5D respectively. No request signal is delivered when the channel 3 gives a request for occupation of bus or another channel is occupying the bus. When the bus becomes idle, the request signal is transmitted. Then the functions of the circuits 5B and 5D are suppressed for the channels 3B and 3D having low priorities. Thus the request passes through these circuits 5B and 5D and reaches the control part 2. After the occupation of bus is once started, the bus occupation request signals can be accepted continuously as much as desired. Thus the occupation of bus is inhibited for other buses. In such a way, it is possible to transfer continuously the data of high priorities.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention provides a high-priority system for high-priority bus management in a plurality of channels connected in a manner that The present invention relates to a data transfer method in which the highest channel can perform continuous data transfer without using a busy signal.

(2) Technical background Normally, using this type of connection method, when the channel with the highest priority attempts to transfer data continuously, a busy signal is output to the other channels. (referred to as interless mode).

(3) Prior art and problems However, with this method, it is not only necessary to provide an output line for outputting a busy signal on the bus line, but also a control circuit for the busy signal is required for each channel. Systems without wires have the disadvantage of requiring extensive modification.

(4) Purpose of the Invention In order to eliminate the above-mentioned drawbacks, the present invention provides a system in which the channel with the highest priority continuously transfers data without using a busy signal output line or its control circuit. The purpose of the present invention is to provide a data transfer method that provides the following advantages.

(5) Structure of the Invention In other words, the present invention continuously outputs a bus occupancy permission signal from the channel with the highest priority to the bus occupancy request line. The channel is configured such that the channel with the highest priority continuously receives the bus occupancy permission signal from the bus management section and performs continuous data transfer.

(6) Embodiments of the Invention The present invention will be specifically explained below based on embodiments shown in the drawings.

FIG. 1 is a diagram showing an example of a data transfer system to which the present invention is applied, FIG. 2 is a circuit diagram showing a bus occupancy request control circuit for a channel with low priority, and FIG. 3 is a circuit diagram showing a bus occupancy request control circuit with the highest priority level FIG. 4 is a circuit diagram showing a channel bus occupancy request control circuit and a time chart showing a data transfer state in a channel having the highest priority.

As shown in FIG. 1, the data transfer system 1 includes a bus management unit 2 and a second enemy channel 3 connected in series to the bus management unit 2 via a bus occupancy request #4.
A, 3B, 3]), ...9, and the channel connected to the terminal side is set to have a higher priority by the bus management unit 2 (therefore, in the case of Fig. 1, the channel 3A, 3B e 31).

The priority is highest in order of... ). As shown in FIG. 3, the bus occupancy request control circuit 5AKtj of the channel 3A with the highest priority is connected to the mountain circuits 6 and 7, the inverter 8, the bus occupancy request section 9, the data transfer command section 1o, and the counter 11. 9. Each low priority channel 3E, 3D
As shown in FIG. 2, the path occupancy request control circuit 5BK of...
The circuit 11 is connected.

In addition, the bus management unit 2Fi, central processing unit f (OPU)
In some cases, the CPU is installed inside the CPU, and in other cases, it is provided independently from the CPU. It goes without saying that the OPU and each channel (including memory) are connected via a so-called common bus.

Since the data transfer system 1 has the above-described configuration, when the channel 3A with the highest priority attempts to continuously transfer data by leapfrogging with the bus management unit 2,
ANDW in control circuit 5A! Set the path occupied internal demand compensation signal I BW8 to "1°" to the i path 6 and output it. AND circuit 6
The other channel 3B.

3D, ... have already occupied the bus line and are transferring data, the occupancy signal OC8 has become "0" via the inverter 8, so the request signal IBW8 #i
Not output, but other channel 3F.

41 if 3D,... are not performing data transfer
Cti, the signal I BW8 is input to the bus occupancy request section 9, and the bus occupancy request signal BW8 becomes °1" and is output to the bus occupancy request line 4. The signal Bvv8 is sent to the adjacent low priority channels 3B and 3D. , . . . are input to the AND circuit 16 of the bus occupancy request control circuit 8 via the inverter 15, and the bus occupancy internal request signal IBW8 in the channels 3B, 3D, . is prohibited, and only signal BW8 of channel 3 is output to OR circuit 1.
7. In this way, the path occupancy request control circuit 8 for channels 3B, 3D, . . . with low priority
through each channel 3B, 3D.

While inhibiting the output of the internal request signal I BW8 of...
The signal BW8 is input to the bus management section 2. The bus management unit 2 receives the signal BW8 and sets the bus occupancy permission signal CC to 11" as shown in FIG. 4 to set the bus clock to 0LOK.
It is output to channel 3 in synchronization with the signal AC (!
The signal is input to the data transfer command unit 10 and the counter 11K via the #1AND circuit 7. The command unit 10 receives the signal AOO
After a short time, a data transfer command DTO is output to the channel, and a predetermined unit of data transfer is performed. However, since the data that can be transferred per signal AOO is predetermined by your company, if more data is sent continuously, Kti
, the channel talk continues to issue an internal request signal IBW8, and thus a request signal BW8, to the request line 4. Then, other low priority channels 3B, 3D, . . . receive internal request signal IB as long as signal BW8 from channel 3A is output
Since W8 is not output to the request line 4 as the signal BW8, the channel talk can continue to occupy the bus line, and the 2 signal output from the bus management section 2 by the request signal B% is The second permission signal AOO is channel 3
A can receive and receive data, and can also transfer data in a predetermined unit continuously, as shown in FIG.

The counter 11Fi counts the number of permission signals AOO sent from the bus management unit 2 side, and when the count value reaches a preset value and the amount of data to be transferred from the channel magazine reaches a predetermined value, the A signal T is sent to the occupancy requesting section 9.
8, and the request unit 9 outputs the request signal BM by the signal T8.
is dropped from @l" to @0"k, and the request line 4 is opened for other channels 3E*3D, . . .k. The signal meat is ``O''
'', the data transfer command unit 10 via the MΦ circuit 7
When the data transfer command D'f'0 is canceled, the value of the 1 counter 11 is reset.

(7) Effects of the invention.

As explained above, according to the present invention, by continuously outputting the bus occupancy request signal BW8 of the three highest priority channels, the request signal BW8 from other channels with lower priority is Since the bus occupancy permission signal AOO from the bus management unit 2 side can be continuously received without using the busy signal output line or its control circuit, It is possible for high-speed channels to transfer data continuously9.
, a system without a busy signal output line, allows continuous data transfer of the highest priority channel without significantly changing the overall system.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a data transfer system to which the present invention is applied, FIG. 2 is a circuit diagram showing a bus occupancy request control circuit for a channel with a low priority, and FIG. 3 is a circuit diagram showing a bus occupancy request control circuit for a channel with the highest priority. FIG. 4 is a circuit diagram showing the bus occupancy request control circuit of FIG. 1...Data transfer system 2...Bus management unit 3A, 3B, 3D,...Channel 4...Bus occupancy request line BW8...・・・Bus occupancy request signal CC ・・・Bus occupancy permission signal

Claims (1)

[Claims] In a data transfer system in which a bus management unit and multiple channels are connected to the bus management unit in a similar manner, a bus occupancy request signal from a high-priority ψ channel is continuously output to the bus occupancy request line. During this period, the bus occupancy request signal is prohibited from being output from the channel with a low priority, and the high-priority channel 1 is prevented from continuously receiving the bus occupancy permission signal from the bus management section. Remove,
A data transfer method configured to enable continuous data transfer.