JPS60199239A - Signal transmission system - Google Patents

Abstract

PURPOSE:To attain miniaturization and high reliability of the circuit by extracting a random code data from a digit on the way of a register array of a CRC arithmetic circuit. CONSTITUTION:The result 32 of CRC operation is fed to a data input terminal D0 of a multiplexer 34 via a NOT circuit 34a from an output terminal of a shift register 332, a random code data 33 is supplied to a D1 from the output terminal of a shift register 316, and an information data 31 is fed to a D2 respectively, they are selected alternatively by a selection signal 35 fed to selection terminals S0, S1 and outputted from an output terminal Q as a trasmission data 36. In such a case, as the transmission data 36, exclusive OR with the result 32 of the said CRC addition is obtained and goes to a CRC operation feedback signal 37, fed to each exclusive OR circuit of the CRC arithmetic circuit to attain CRC calculation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission control device that transmits and receives digital data signals, and particularly relates to a signal transmission system that enables miniaturization and high reliability of circuits.

[Prior art]

In well-known JJ and JJ communication, data transmission is often performed by configuring a frame 1 as shown in FIG.

In this figure, 11 is the start delimiter (Ihl start nolag) that accepts the start of the frame, 12i is the destination address that indicates the destination station, 13 is the Sanskrit address that indicates the originating station, and 14 is each Mia, 11 and 13. 15 is the transmission data, 16 is the padding data added when the frame is extremely distorted, 17 is the frame detection Mm code for code error detection, and 18 is the end delimiter (the end of the room). flag).

The reason why the padding data 16 is added here is to prevent problems in transmission control from occurring if the sending data 15 is extremely short.
In order to avoid the uniqueness of the same code, a signal that is as close to a random signal as possible is required. Further, as the frame check code 17, generally CRC (Cyclic
An error check code based on the redundancy C1+eck) method is adopted, and the transmission (S fa
It is necessary to perform one error check rq over the entire issue.

At the top of this conventional scale, there is a CRC generator [i1!
Since the random code generating circuit for generating the padding data 16 and the random code generating circuit for generating the padding data 16 are separate circuits, there is a disadvantage in that the circuit becomes large in size.

(Objective of the Invention) In view of the above-mentioned circumstances, the present invention provides a signal transmission method that enables miniaturization and high reliability of circuits.

[Characteristics of chewing]

In order to achieve this object, the present invention extracts random code data from the loss in the register string of the CRC arithmetic operation, thereby generating a random code (padding data 16) and a CRC code (frame check code). 1' January 17) is generated and transmitted only by the CRC processing circuit.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of one embodiment of the present invention.
ICT 802 LOCAL NETWORK ST
A N D A R D S D R A F D C” 1
．． : The CRC decoder circuit in the case of CRC-32 in iJ M
be. In FIG. 1, 301 to 332 are shift registers each having a length of 1 bit, .largecircle. indicates an exclusive OR circuit, and .largecircle. indicates a NOT circuit. It is also a 3/I fJ multiplexer, and sends 4Q reverberation information data 31. C
I Cii'j result 32, random code data 33
It selects one option and outputs it. g <r, Maru f Plexer 34 data head o = r) o receives the CRC operation result 32 from the output end of the register 332 via the negation circuit 34a, and Dl receives the register 1~.]
Random n>→ data 33 from the 1G output terminal is transferred to D2
is the information data (this is the destination address 12 shown in Figure 1).
- Transmission data 15) (generic term) 31 are respectively supplied, and these are selected by the selection signal 35 supplied to the selector terminal So, 81. Output from @Q. .

In this case, the sending 18 data 36 is the CRC addition result 32.
Do4. i 11! ! CI'< C
f is performed.

In such a configuration (1η), when the start delimiter 11 shown in FIG. At the same time, the CRC operation of the above data is performed in parallel.Next, select (change g 35, select random tT?r data 33, add padding data 1G, etc.) A long transmission is performed, and the CRC1ilfi Gti is performed at the same time.Then, after transmitting the padding data 16, the selection signal 35 is changed again to select the CRCii calculation result 32, which is transmitted as the frame check code 17, and finally terminated. The delimiter 18 is transmitted to complete the transmission of one frame.

According to this embodiment, the CRC calculation result 32 signal data 3G iJl logical disjunctive signal 37 is fixed to 0 or 1 degree. Since there is no such thing, data 33 b for random 1 code
161 It's hard to say what's going on in the fixed berth.
Near random pick as 6]・Column is 1q. In addition, in the above example, the extraction position of the data 33 for No. 1 sink L?: 2 was explained for the case where the extraction blade is from the 16th bit, but the child p20 position of the 1st bit to the 31st bit is Is it possible to get the same effect even if you take it out of your neck? (・Saru.

〔Effect of the invention〕

As explained above, according to this specification, CI<C
Since the arithmetic circuit can be used for both CRC calculation and random IUT data at the same time, it is possible to reduce the size of the transmission circuit when transmitting data that requires bubbling data. Also, padding can be included in the CRC function of the transmitted data, so
Even in the case of publishing transmission, errors in transmission can be checked without breaking the standard frame format (--this can contribute to high transmission reliability).

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the configuration of room 1, and FIG. 2 is a block diagram showing the configuration of the CRC) Ji E1 circuit according to an embodiment of the present invention. 1G...Padding data (random code),
17...-Room check code, 33...
Random code data (signal extracted from a digit in the middle of the register string of the CRC binding circuit), 301 to 332...
...Schiff 1 heregisk (register row). Applicant Nippon Telegraph and Telephone Public Corporation Mitsubishi Electric Co., Ltd. Toshu Shibaura Electric Co., Ltd.

Claims (1)

[Claims] Sending 4:X-! A random code is added to the data, and a frame check code (=
In a signal transmission method in which J is added and transmitted, a signal extracted from a digit in the middle of the register string of the CRC calculation circuit is transmitted as the random code, and then a frame check code calculated including this random code is transmitted. It is characterized by Jru (g8deni;!D'j style.