Serial data transmission between redundant channels

• US 5,093,910 A
• Filed: 05/31/1991
• Issued: 03/03/1992
• Est. Priority Date: 10/29/1986
• Status: Expired due to Term

• Current Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Tulpule, Bhalchandra R., Binnall, Daniel G.
• Primary Examiner(s): Shaw, Gareth D.
• Assistant Examiner(s): KULIK, PAUL V
• Application Number:
  US07/708,802
• Time in Patent Office: 277 Days
• Field of Search: 364/200 MS File, 364/900 MS File, 364/200, 364/900, 371/68.1
• US Class Current: 714/56
• CPC Class Codes: G06F 13/18 based on priority control G06F13/1605 takes precedence
• CPC Class Codes: G06F 13/30 with priority control

Abstract

Data is communicated between redundant channels formatted in blocks having an initial command word followed by a destination code, starting address and a variable number of data words including a word count. The blocks are transmitted between each channel and all of the channels over cross-channel data links, each channel receiving the data blocks and determining the validity thereof by counting the number of data words received and comparing that number to the word count transmitted for that block. An interrupt signal indicative of invalidity of a block is provided in the event of a miscompare. A stop address is generated for each block received for storage at the start address. A memory address is generated for each valid word received for storage in sequence starting immediately after the start address. The next block received has its start address placed immediately at the end of the previously received block.

Claims

1. A method for use in each channel (10) of a redundant channel control system for gathering and communicating redundant data signals between channels over cross-channel data links (64, 69), the method comprising the steps of:

gathering one or more data signals (36, 48, 56 or

     30) by means of one or more corresponding devices (42, 46, 54 or

     28);

storing the gathered data signals as data words in input/output (I/O) memory (18) under the control of a Direct Memory Access Controller (14) for transmission over the cross-channel data link (64);

transferring data words from the I/O memory (18) to a link transmitter (62) under the control of a link interface controller (22) for said transmission;

formatting the data words in data blocks, each block having an initial command word having a command word identifier protocol followed by an origination code and a starting address, the command word followed by a variable number of other words, the first other word having a data word identifier protocol followed by a word count, the second and remaining other words each having a data word identifier protocol followed by data words;

transmitting the transferred data words in the formatted blocks from the link transmitter to link receivers (24) in all of the channels over the cross-channel data links;

receiving the transmitted data word blocks in the link receiver;

providing, by means of the link interface controller, memory address signals for storing the received data words in link memory (26) allocated according to the channel from which the associated block of data words originated and for storing the starting address in link memory in the next available sequential memory location after the end of the previously received block for providing a stop address according to the starting address plus the word count and for storing in link memory the stop address at the starting address and for storing, in link memory, each subsequently received data word of the block sequentially after the starting address.

2. A method for use in each channel (10) of a redundant method control system for communicating redundant data between a plurality of channels, comprising the steps of:

gathering channel-related data by means of one or more types of devices (42, 46, 54, Or

     28) for transmission in blocks of data words;

transmitting said blocks to the other ones of the plurality of channels by means of a link transmitter (62) over cross-channel data links (64);

receiving transmitted blocks from other channels by means of a link receiver (24);

storing received blocks in channel memory, allocated by channel, by means of a link controller (22) wherein each received block has one or more initial word signals at least having a group of channel origination code signal bits ("origination code"), a number of start address signal bits ("start address pointer") and a series of word count signal bits ("word count"), all remaining data words of each block each having a group of data signal bits, wherein said step of storing a received block comprises;

storing the "start address pointer" obtained from each received data block at the next available memory location following the last block stored in a subsection of memory corresponding to the origin of the data block received as indicated by the "origination code";

generating a stop address pointer by adding the magnitude of the "start address pointer" to the "word count";

storing the stop address pointer at the address ("start address") pointed to by the "start address pointer"; and

storing subsequently received data words in the corresponding data block at sequential memory locations after the "start address".

3. A memory storage method for use in a redundant channel control system for storing received data words grouped in blocks transmitted from a channel to other channels, comprising the steps of:

receiving, by means of a link receiver (24) in each channel, a data block transmitted from any of the redundant channels;

determining, in a link controller (22), the channel from which the received data block originated; and

storing, by means of the link controller (22), the received block of data words in a link memory (26) allocated according to the determination of channel original wherein each block has one or more initial word signals at least having a group of channel origination code signal bits ("origination code"), a number of start address signal bits ("start address pointer") and a series of word count signal bits ("word count"), all remaining data words of each block each having a group of data signal bits, wherein said step of storing comprises the substeps of;

storing the "starting address pointer" obtained from each received data block at the next available link memory (26) location following the last bock stored in a subsection of link memory (26) corresponding to the origin of the data block received as indicated by the "origination code";

generating a stop address pointer by adding the magnitude of the "start address pointer" to the "word count";

storing the step address pointer at the address ("start address") pointed to by the "start address pointer"; and

storing subsequently received data words in the corresponding data block at sequential link memory locations after the "start address".

4. Memory storage apparatus for use in each channel (10) of a redundant channel control system for storing asynchronously received digital words grouped and transmitted serially in blocks from any channel to other channels, comprising:

a link receiver (24), responsive to a block having a start address word, a word count word, and a plurality of data words from the transmitting channel, for storing the words of the block, for providing a transfer request signal for each word and for providing the words in a series in response to a corresponding series of transfer demand signals;

a link interface controller (22), responsive to said transfer request signals for providing said transfer demand signals, for storing said words, for determining the identity of the transmitting channel, for providing a sequence of addressing signals for storing said start address in the next available sequential memory location after the end of the previously stored block, for providing a stop address by adding the start address to the word count, for storing said stop address at the start address, and for storing said data words starting at the next available location after the start address and each subsequent data word in sequential memory locations; and

a link memory (26), responsive to said sequences of addressing signals and words, for storing said words at the addressed memory locations, the memory thus being allocated for storage of blocks according to said identity of the transmitting channel.

5. The apparatus of claim 4, wherein alteration or storage of words in the link memory (26) is achieved only by receiving words from the link receiver (66) through the link interface controller (22).

6. The apparatus of claim 4, wherein said link receiver is responsive to a block transmitted from all of the redundant channels, including the channel of said link receiver.

7. Apparatus comprising a plurality of channels, each channel comprising:

a plurality of data signal input means (42, 46, 54,

     28);

a link memory (26);

a Direct Memory Access (DMA) memory (18);

a DMA controller (14) for transferring data signals received by any of said input means to said DMA memory;

link transmitter means (62);

link receiver means (24);

a plurality of cross-channel links (64,

     69) for interconnecting said link transmitter means with said link receiver means and with similar link receiver means in each other one of said plurality of channels; and

a link interface controller (22) for transferring data signals from said DMA memory to said link transmitter means in data blocks for transmission to all of said link receiver means over said cross-channel data link, said link interface controller for formatting said blocks with a start address, a word count, and data words, and for storing data blocks received by said link receiver means of the related channel in said link memory by storing the start address in the next available location after the end of the last stored block, by storing at the start address a stop address and by storing the data words at sequential locations, all within a segregated portion of said link memory corresponding to the one of said channels from which said data block was transmitted over said cross channel links.