JPH0527899B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a data transmission device that transmits data between systems that mainly operate asynchronously.
In particular, the present invention relates to a data transmission device that selectively branches data conditionally. [Prior Art] Conventionally, a common method for transmitting data between asynchronous systems was to use FIFO (first-in, first-out) memory as a buffer between systems (interface
(See August 1984 issue, pages 268-270). for example,
When transmitting data between the A system and the B system which operate asynchronously, as shown in FIG. 8, a FIFO memory 3 is connected between the output of the A system 1 and the input of the B system 2. A system 1
A configuration is adopted to buffer the output of. Further, when data is transmitted between a plurality of asynchronous systems, a configuration is adopted in which FIFO memories 8 to 10 are connected between each asynchronous system 4 to 7, as shown in FIG. By the way, in conventional data transmission devices, FIFO memory only has a data buffering function, so if such FIFO memory is used for data transmission between asynchronous systems, multiple asynchronous systems can only be connected in series. As a result, the overall system connected by FIFO memory consists of a simple pipeline processing mechanism using cascade connections, which has an extremely low degree of freedom. In response, the applicant has developed and filed an application for a data transmission device that can provide greater flexibility when constructing an entire system by connecting asynchronous systems (Japanese Patent Application No. 60-33035). , Tokugansho
60-33036). This uses asynchronous self-propelled shift registers to configure input data transmission paths, output data transmission paths, branch data transmission paths, and merge data transmission paths, and determines whether the data on the input data transmission path is data that should be branched. is judged by a branch judgment means, and if the data should be branched, the data is given from the input data transmission path to the branch data transmission path, and otherwise, the data on the input data transmission path is given to the output data transmission path. On the other hand, when there is an empty buffer on the input and output data transmission paths, the data on the merged data transmission path is given to the output data transmission path, so that asynchronous systems can be connected not only in series but also in parallel. This is what I did. [Problems to be Solved by the Invention] However, in the above-mentioned data transmission device, the data branching conditions are treated as fixed, and changes in the operating state are not considered at all. There was a problem in that branching conditions could not be arbitrarily set during initialization, which was undesirable in terms of processing flexibility. The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a data transmission device that can change data branching conditions in an operating state. [Means for solving the problem] The first invention of the present application configures the input data transmission line, the output data transmission line, and the branch data transmission line using self-propelled shift registers, and A branching determination means for determining whether the data on the input data transmission path is branch data; and a branching control means for normally applying the data on the input data transmission path to the output data transmission path, and when it is branch data, to the branch data transmission path. , branching condition changing means is provided for detecting specific data having a specific identifier when inputted to the input data transmission path and changing the branching condition of the branching determination means in accordance with the data. be. A second invention of the present application is, in addition to the first invention, provided with specific data erasing means for erasing specific data after the branch determining means changes the branch condition. [Operation] In the first invention, when specific data having a specific identifier is input to the input data transmission line during operation of the device, the branch condition changing means detects this and changes the branch condition of the branch determining means. and thus the branching conditions are changed in the operating state. Further, in the second invention, the branch condition is changed by specific data while the device is operating, and then the specific data erasing means erases the specific data, and thus the branch condition is changed and the specific data is erased in the operating state. It is something. [Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1 to 7 show a data transmission device according to an embodiment of the second invention of the present application. FIG. 1 shows an overall configuration diagram of this embodiment, and in the figure, 11a, 11a,
11b, 12, and 13 are input data transmission lines, output data transmission lines, and branch data transmission lines configured using asynchronous self-running shift registers; 14 is a data transmission line that outputs the data on the input data transmission lines 11a and 11b; 12 or a branch control section 15 which supplies the branch data transmission line 13 with branch conditions set in advance;
a branch determining unit 17 which compares this with the conditions of the data on the input data transmission path 11b and provides a branch control signal to the branch control unit 14 when the two match;
detects specific data on the input data transmission path 11a when specific data having a specific identifier is input to the input data transmission paths 11a and 11b,
A branch condition changing section 18 changes the branch condition of the branch determining section 15 in accordance with the data, and a specific data erasing section 18 erases specific data after changing the branch condition. In addition, FIGS. 2 and 3 show the input data transmission line 11.
11b, an example of an asynchronous self-running shift register used for the output data transmission line 12 and the branch data transmission line 13. In Figure 2, 19 is a parallel data latch, 20 is a 3-input NAND 21, 2
This is a transfer control circuit (hereinafter referred to as C element) which is configured by input NANDs 22 and 23 and provides a rising edge trigger to the parallel data latch 19. An asynchronous self-running shift register is a register that automatically shifts input data in the output direction without using a shift clock, provided that the next register is empty, and it is a register that automatically shifts input data in the output direction without using a shift clock. It has a function. This asynchronous free-running shift register is a parallel data latch 19.
and a C element 20, and the C element 20 is P
It receives two inputs, 0 and P3, and outputs two outputs, P1 and P2, and the internal state of the C element 20 is determined by the states of these four signals P0 to P3, as shown in the table below. takes nine states S0 to S8. In the following description, it is assumed that logical values 0 and 1 correspond to low level and high level signal values, respectively.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to perform selective branching in a data transmission device, and the branching conditions can be changed by passing specific data during operation, thereby providing processing flexibility. It has the effect of significantly improving

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a data transmission device according to an embodiment of the second invention of the present application, and FIGS. 2 and 3 both show circuit configurations of an example of an asynchronous free-running shift register used in the above device. Figures 4 and 4 are diagrams for explaining the functions of this asynchronous self-propelled shift register, Figures 5a and b are both concrete circuit configuration diagrams of the above device, and Figure 6 explains the operation of the above device. FIG. 7 is a diagram showing the structure of a specific data packet used in the above device, and FIGS. 8 and 9 are diagrams showing a conventional data transmission device. 11a, 11b...input data transmission path, 12...
...output data transmission line, 13...branch data transmission line, 14...branch control section, 15...branch determination section,
17...Branch condition changing unit, 18...Specific data erasing unit. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. A data transmission device that performs data transmission between systems, which includes a plurality of data latches and transfer control at each stage that controls its own data latch according to control signals from transfer control circuits at adjacent stages. An input data transmission path, an output data transmission path, and a branch data transmission path configured using a self-propelled shift register consisting of a circuit, and whether or not the data on the input data transmission path is data that should be branched based on the set branching conditions. a branching determining means for determining the data on the input data transmission path, and normally applying the data on the input data transmission path to the output data transmission path, and when the branching determining means determines that the data on the input data transmission path is data to be branched, the data is branch control means for applying to the branch data transmission path; and branch judgment means for detecting specific data on the input data transmission path when specific data having a specific identifier is input to the input data transmission path, and depending on the data. A data transmission device comprising a branch condition changing means for changing a branch condition of the data transmission device. 2. A data transmission device that transmits data between systems, which is a self-running type consisting of multiple data latches and a transfer control circuit at each stage that controls the data latch at each stage according to control signals from the transfer control circuit at the adjacent stage. An input data transmission path, an output data transmission path, and a branch data transmission path configured using shift registers, and a branching determination means for determining whether data on the input data transmission path is data to be branched based on a set branching condition. Usually, the data on the input data transmission path is applied to the data transmission path, and when the branch determining means determines that the data on the input data transmission path is data to be branched, the data is applied to the branch data transmission path. branching control means; and branching for detecting specific data on the input data transmission path when specific data having a specific identifier is input to the input data transmission path and changing the branching condition of the branching determination device in accordance with the data. Condition changing means,
A data transmission device comprising: specific data erasing means for erasing the specific data after a branch condition change in the branch determining means.