JPS63182939A - Communication control equipment - Google Patents

Abstract

PURPOSE:To cope with the revision or addition of a communication control function flexibly by executing the communication function of a high-order level according to the system control program of a semi-fixed storage means and a communication control program transferred from a host device in the case of initializing. CONSTITUTION:In the initializing state, a processor 106 of a communication controller 100 sends a program transfer request to an operation controller 202 via a control line of a port 1 according to the control of a system control program of a ROM 108. A buffer control circuit 120 of the communication controller 202 stores once the program and data into a buffer 104. A processor 108 reads a communication control program from a buffer 104 according to the instruction of the system control program of the ROM 108 and stores it in a variable program storage area 302 of a RAM 110. The function having the possibility of revision or addition in the function is stored in the RAM 110 in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to communication control method 2, particularly a communication control device suitable for a communication system that performs high-level data link control.

(Prior Art) For example, CCITT Recommendation There was an x,25 control LSI that realized the lower functions of 2 and 2 using hardware, and the upper m plows using firmware. For example, see "Technology Transfer Special Seminar Text r Packet Switching Network J" published by Japan Communication Technology Co., Ltd., pp. 30-31 (March 1985).

Such a communication system DI LSI consists of a line control unit that interfaces with a line, a logical operation unit that performs logical operations such as packet assembly, and a memory interface unit that interfaces with a host processor in the form of a data channel. has been done. Sub-functions included in Recommendation x, 25 levels l and 2, namely flag synchronization, rOJ
Insertion/deletion, frame check sequence (Fe2) inspection/generation, etc. are performed by hardware. In addition, lower-level functions such as frame creation, analysis, and state control are performed by firmware. The firmware is stored as a microprogram in the ROM in the logic operation section.

When receiving data from the line, detection of a flag pattern indicating the start of data, detection of an FCS code indicating the end of information, deletion of "0" from the address (A) part and control (C) part of the IDLC frame, Error checking and control of received data and retransmission requests are performed by the line control section. Analysis of address parts and control parts,
The next process to be executed and the state ffi transition destination are determined by the ROM firmware of the logic operation section. The information (I) part following the control part is transferred to the main memory designated by the host processor, and this transfer is performed under the control of the DMA (direct memory access) circuit of the memory interface section.

When transmitting data to a line, the logic operation section of the communication control LSI detects whether the data transmission from the host processor is stable,
and creation of address part and control heart by RO
This is done using M's microprogram. The memory interface section also reads transmission information from the main memory specified by the host processor under the control of the DMA circuit. The line control unit performs rQJ insertion control, creates an FCS code, and sends assembled packets to the line.

In this manner, in the conventional communication-based g#LSI, the data transmission and reception operations are shared between the LSI's hardware and firmware. This is because the functions at levels 1 and 2 are relatively simple and have been standardized.

(Problem to be Solved by the Invention) However, in such a conventional communication control LSI, in order to change or add a communication control device, the hardware and firmware of the LSI itself must be changed accordingly. There wasn't. This is an integrated circuit communication control LS
This involves changing the design of I, which requires a considerable amount of man-hours and costs. In particular, in order to incorporate changes into a communication system that is in operation, it is necessary to temporarily suspend the service and replace the communication control LSI with a new one.

The present invention provides communication control LSI at? It is an object of the present invention to eliminate such problems of the conventional technology with respect to changes and additions, and to provide a communication control device that is flexible with respect to changes and additions of functions.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a communication control device that is connected between a host device and a transmission device and performs high-level data link control. The processing device has a communication circuit that is connected to the device and executes the communication function of the lower level using wired logic, and a processing device means that is connected to the upper device and executes the communication function of the upper level by storage program control. The means includes a semi-permanent storage means for semi-permanently storing fixed information, a temporary storage means for temporarily storing variable information, and a temporary storage means for receiving variable information from a host device and temporarily storing it in the temporary storage means. The fixed information includes a fixed control program of the communication control device, and the variable information includes a transfer means.
Contains a variable control program specific to the communication control device,
When the communication control device is initialized, the information is transferred from the host device to the transfer means and stored in the temporary storage means by the transfer means.

(Function) For example, a plurality of communication control bags δ are commonly housed in a host device, and the host device has a storage means in which variable information about all of the plurality of communication control devices is stored. This communication variable information includes a variable control program unique to each communication control device, and is transferred from the storage means of the host device to the transfer means of the communication control device when the communication control device is initialized. The data is stored in the temporary storage means by one stage of transfer. The processing device means performs higher level communication functions in accordance with the system control program stored in the semi-permanent storage means and the communication control program stored in the temporary storage means.

(Embodiment) In order to better understand the features of the present invention, an example of a conventional communication control LSI will be described with reference to FIG. 4 prior to a detailed description of the present invention. This communication control LSI 10 is -L
It is connected between a processor bus 16, which is connected to the processor 12 and the main memory 14, and a line, and is configured as a single LSI.

This includes a line control section 18 that interfaces with the line, a logic operation section 20 that performs logic operations such as packet assembly, and a memory interface section 22. The interface with the host processor 12 is in the form of a data channel, and data transfer is performed by sending and receiving commands and status information.

As mentioned above, the lower functions of levels 1 and 2 of Recommendation The firmware is implemented in the ROM of the logic operation unit 20 as a microprogram.

When data is received from the line, the line control unit 18 detects a flag pattern and detects the address of the HDLC frame (A
) part and the control (C) part, and transfers the received data to the logic operation section 20. The logic operation unit 20 is configured to perform A by the firmware of the ROM.
The part and C part are analyzed to determine the next process to be executed and the state transition destination. Information following part C (I)
The D part of the memory interface unit 22 is transferred to the storage area of the main memory 14 specified by the host processor 12.
When the 0-line control unit 18 detects the FCS code,
Based on this, the received data is checked for errors, and if normal, this is reported to the host processor 12 and the series of receiving operations is completed. Note that if data cannot be received correctly due to a transmission error or the like, the line control unit 18 requests the opposing device to retransmit.

When transmitting data to the line, when the logic operation unit 20 of the communication control LS 110 detects a data transmission request from the host processor 12, it creates part A and part C under the control of the microprogram in the ROM. The memory interface unit 22 reads information to be transmitted from the main memory 14 designated by the host processor 12 using the DMA control circuit. The line control unit combines the transmission information with the A part and C part, inserts "0", and sends it to the line. An FCS code is added to the end of the transmission information, and the transmission operation is completed. Communication control LSI 1 according to this conventional example
0, data transmission and reception operations were performed by hardware and firmware.

Next, embodiments of a communication control device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 shows a configuration example of a communication system to which a communication control device according to the present invention is applied. This communication system communicates from the transmission device to the opposite device through a line using the H[lLC procedure, and has two ports.
+1 communication control device 100 is connected between a transmission device (not shown) and a host device. The host device is a host control device 2 that includes a processor similar to the processor 12 shown in FIG. 4 and a main memory similar to the main memory 14.
00 and the continuous control device i!, which will be described later. ! 0 consisting of 202
The line side of the communication control device 100 is connected to the transmission device by a communication line 102, and is finally connected to the opposite device through the line.

Communication control device 100 has two boats, boat 0 and boat l. The former is processor bus 20
4 to the upper control device 2!1200, and the latter is connected to the operation control device 202 via the processor bus 206.

Referring to FIG. 1, a communication control device 100 is a control device that controls the transmission and reception of information according to the HDLC procedure in accordance with the communication rules or protocols defined between the communication control device and the opposing device via the transmission device. This consists of a communication control LS 1103 that transfers transmission/reception information to and from the higher-level device, and n buffer circuits (BF) 104 for temporarily storing the transfer information exchanged between the higher-level device and the higher-level device. There is.

The buffer circuit 104 is a temporary storage device that temporarily stores information to be transmitted and received from each other device, and has an n-plane configuration in this embodiment. Each of these snow pipes 1 to lln can operate independently. The buffer circuit 104 is
Internal bus 112 . Transmitting device (SEND) 114. Receiving device (RFC) 11
B and upper device interface section (INF) 122
It is connected to the. The buffer control circuit (
BFC:TL) 120.

The communication control LsI 103 is configured such that a considerable time delay is not allowed and fixed functions are realized by wiring logic, and other functions are executed by storage program control. For example, HDL
C-frame detection and transmission.

There is rQJ deletion and insertion, FCS code detection and generation. The function realized by the wiring logic is a transmitting/receiving function with strict real-time characteristics, and such communication is shared by the hardware of the transmitting device ri 114 and the receiving device fi 11B.

In order to realize the function through storage program control, the communication control LSI 103 is connected to a processor (P) as shown in the figure.
108. Read only memory (ROM) 108 and random access memory (RAM) 11 (l)
They are interconnected by an internal bus 112. Processor 106 includes ROM 108 and RAM
This is a storage program controlled processing device that controls and integrates the entire LSI 103 using the LSI 110.

When the transmitter 21114 receives a transmission request from the processor 106 through the I10 controller 118, the transmitter 21114 transmits the buffer circuit 1.
The information stored in 04 is read out sequentially, and rQ
It has the function of assembling a transmission frame by inserting J and adding an FCS code, and sending it out from the transmission line 102a to the line via the transmission equipment. The receiving device 116 detects the transmission frame from the line received from the receiving line 102b, deletes the "0" included in it, and performs error checking such as FCS error and Ogt error checking, and fills the buffer. 104 to load the received information. When the start flag of the transmission frame is detected, a reception request is issued to the processor 106 through the I10 control unit 118.

ROM 10B and RAM 110 are processor 1
It constitutes the main storage area used by 06. In this embodiment, the main storage area is a permanent program storage area 300. It consists of a variable program storage area 302 and a work area 304. In this embodiment, the immutable program storage area 300 is a system that executes system control g# functions, such as information transfer control with a host device, which is not affected by changes or additions to the functions of the communication control device 100. This is a storage area in which fixed information such as control programs is stored, and is defined in the ROM 10B, which is a semi-permanent storage device. That is, the firmware programs used by processor 106 are stored therein.

The variable program storage area 302 is a storage area for storing variable information such as programs whose functions may be changed or added, for example, communication control programs, and the work area 304 is a work area used by programs running on the processor 10B. It is. Both areas 302 and 304
is formed in RAM 110, which is a temporary storage device.

In this embodiment, these main storage areas are assigned a series of storage location addresses as a whole, as shown in FIG.

The area 300 has memory addresses r0OOOJ~r3
FFFJ (hexadecimal number), memory addresses r4000J to r7FFFJ are assigned to the area 302, and memory addresses r8000J to rFFFFJ are assigned to the area 034.

I10 control unit 118 is a circuit that interfaces transmitting device 114 and receiving device 116 with internal bus 112. The higher-level device interface unit 122 is a circuit that accommodates two boats, namely, boat 0 and boat 1, and interfaces with the higher-level control device 200 and the operation control device 202, respectively.

The internal bus 112 also includes an interrupt control circuit (INTO).
124 and a timer (IN) 126 are also connected.

The interrupt control circuit 124 is a circuit that controls interrupts related to the processor 10B, and the timer 126 is a circuit that controls interrupts related to the processor 10B.
This is a circuit that generates timing used in the program executed by 08.

Of course, these communication control LS1103
Each engine part that constitutes the
In this example, as the name suggests, the part surrounded by
are integrated as multiple semiconductor devices to form one large-scale integrated circuit.

By the way, the continuous control device 202 shown in FIG. 2 includes a processing device and a storage device (not shown). The storage device may be a file storage device, such as a floppy disk, which includes the $0.00
RAM 11 of each communication control device 100 up to 1lfi
Variable programs to be stored in the 0 area 302, such as communication control programs and data, necessary for the communication system are prepared and stored. These programs and data are always updated and prepared according to the system status.

When a particular communication control device 100 is installed in a system and powered on, the system is initialized. In initialization, the processor 106 of the communication control device 100 first communicates with the operation control device 202 via the control line of the boat 1 under the control of the system control program in the ROM 108.
Sends a program transfer request to. Operation control device 202
When the processing device accepts this request, it sequentially reads the communication control program and data corresponding to the requested communication control device 100 from the storage device and sends them to the communication control device 202 through the data line of the boat l. do.

The buffer control circuit 120 of the communication control device 202 temporarily stores these programs and data in the buffer 104. When the operation control device 202 finishes sending the necessary programs and data, it sends a program transfer completion indication to the control line of the boat 1. The processor 106 detects this, reads the communication control program from the buffer 104 according to the instructions of the system control program in the ROM 108, and stores it in the variable program storage area 302 in the RAM 110. Upon completing this, the processor 106
A transition is made to a normal operating mode or state in which information can be transmitted and received between the second position system '4Jg device 200 and the opposing device through the transmission device.

The information to be transmitted is the 4th second control device i! 1200 to boat O through the data line of processor path 204. This is stored in a designated storage surface of the buffer circuit 104 from the host device interface section 122 through the buffer control circuit 120. Prose 2 106 there,
A communication control program is executed under the management of the system control program, and a transmission request is issued to the transmitting device 114 through the I10 control unit 118.

In response, the transmitter 114 sends the buffer circuit 104
The information stored in the frame is sequentially read out, "0" is inserted into it, an FGS code is added, etc., and the frame is assembled into a transmission frame, and the frame is sent out from the transmission line 102a to the line via the transmission device.

On the other hand, when a transmission frame is received from the reception line 102b,
The receiving device 116 detects this and contains "
The received information is loaded into the buffer 104 while deleting "0" and performing error checks such as FCS error and octo error checks. When the start flag of the transmission frame is detected, a reception request is sent to the processor 10B through the I10 control unit 118. The processor 10B sends this reception request to the host controller 2t 200 through the control line of the boat O.
Notify the person accordingly. The received information is transferred to the higher-level control device 200 from the buffer circuit 104 through the higher-level device interface section 122 and the data line of the boat O under the control of the buffer control circuit 120.

In the main memory layout shown in FIG. 3, the system control program is stored in the constant program storage area 300, and the communication control program is stored in the variable program storage area 3.
It is stored in 02. However, even in communication control programs, fixed parts or parts with little possibility of change are R.
The program may be configured to be stored in the permanent program storage area 300 of the OM 108.

Conversely, a variable part of the system control program, that is, a part that may be changed, may be stored in the variable program storage area 302 of the RAM 110. In the latter case, such a system control program is also prepared in the storage device of the operation control device 202 and is stored in the communication control device 100 as in the case of the communication control program.
When initializing the communication control unit 1 from the operation control unit 202
00 RAM 110. In addition, a similar method can be used not only for such programs but also for data necessary for the operation of the communication control device 100.
Fixed data is stored in the area 300 of the ROM 108, and variable data is stored in the RA from the operation control device 302.
It may be configured to be stored in the area 302 of M 110.

As described above, according to this embodiment, the communication control device 100
Highly real-time and fixed functions are realized using wiring logic,
Other features are configured to be executed under storage program control. Functions that are not affected by changes or additions to the functions of the communication control device 100 are stored in the ROM 108 as firmware. Furthermore, functions that may be changed or added to the five functions are stored in the RAM 110. This is done by the operation control device 202 during initialization.
110.

(Effects of the Invention) As described above, according to the present invention, a highly versatile communication control device that can be applied to various communication control procedures is realized, and therefore, changes and additions to communication control functions can be flexibly handled. Furthermore, such additions and changes can be made without stopping other systems in operation.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing an embodiment of a communication control device according to the present invention, FIG. 2 is a relay system diagram showing a configuration example of a communication system to which the communication control device according to the present invention is applied, and FIG. A memory layout diagram showing the memory layout of the main storage area in the embodiment shown in the figure, and FIG. 4 is a functional block diagram showing an example of a conventional communication control LSI. Explanation of symbols of main parts +00. , , Communication control device 104...7771 circuit 1013, , Processor 108, , ROM 110, , RAM 114, , Transmitting device 11B, , Receiving device 202, , Operation control device 300, , Unchanged Program storage area 302...Variable program storage area Patent applicant: Oki Electric Industry Co., Ltd. Agent: Katori, Iriyama Takao, 1 (1 credit, 212 memory 7r, father) 911 of Jugi 1 ke 73 concave

Claims (1)

[Claims] 1. A communication control device that is connected between a higher-level device and a transmission device and performs high-level data link control, the communication control device being connected to the transmission device and having lower-level communication functions. a communication circuit that executes the communication function using wired logic; and processing device means that is connected to the higher-level device and executes the upper-level communication function under storage program control; a temporary storage means for temporarily storing variable information; and a transfer means for receiving variable information from the host device and temporarily storing it in the temporary storage means. The fixed information includes a fixed control program for the communication control device, and the variable information includes a variable control program specific to the communication control device, and the variable information includes a variable control program specific to the communication control device, and When it comes to
A communication control device characterized in that the information is transferred from the host device to a transfer means and stored in the temporary storage means by the transfer means. 2. The communication control device according to claim 1, wherein the fixed control program includes a system control program for the communication control device, and the variable control program includes a communication control program for the communication control device. Communication control, wherein the processing device means executes the higher level communication function according to a system control program stored in the semi-permanent storage means and a communication control program stored in the temporary storage means. Device. 3. In the communication control device according to claim 1, a plurality of communication control devices are commonly accommodated in the higher-level device, and the higher-level device controls the variable control device for all of the plurality of communication control devices. 1. A communication control device, comprising a storage means in which information is stored.