From: archamba@ERE.UMontreal.CA (Archambault Benoit)
Newsgroups: comp.sys.m68k
Subject: S1-S9 etc ...
Date: 7 Jan 93 16:47:52 GMT
Organization: Universite de Montreal


     SREC(4)                UNIX 5.0 (03/21/84)                SREC(4)



     NAME
          srec - S-record file and record format

     DESCRIPTION
          An S-record file consists of a sequence of specially
          formatted ASCII character strings.  An S-record will be less
          than or equal to 78 bytes in length.

          The order of S-records within a file is of no significance
          and no particular order may be assumed.

          The general format of an S-record follows:

          +-------------------//------------------//-----------------------+
          | type | count | address  |            data           | checksum |
          +-------------------//------------------//-----------------------+



          type      A char[2] field.  These characters describe the
                    type of record (S0, S1, S2, S3, S5, S7, S8, or
                    S9).
          count     A char[2] field.  These characters when paired and
                    interpreted as a hexadecimal value, display the
                    count of remaining character pairs in the record.

          address   A char[4,6, or 8] field.  These characters grouped
                    and interpreted as a hexadecimal value, display
                    the address at which the data field is to be
                    loaded into memory.  The length of the field
                    depends on the number of bytes necessary to hold
                    the address.  A 2-byte address uses 4 characters,
                    a 3-byte address uses 6 characters, and a 4-byte
                    address uses 8 characters.
          data      A char [0-64] field.  These characters when paired
                    and interpreted as hexadecimal values represent
                    the memory loadable data or descriptive
                    information.

          checksum  A char[2] field.  These characters when paired and
                    interpreted as a hexadecimal value display the
                    least significant byte of the ones complement of
                    the sum of the byte values represented by the
                    pairs of characters making up the count, the
                    address, and the data fields.

          Each record is terminated with a line feed.  If any
          additional or different record terminator(s) or delay
          characters are needed during transmission to the target
          system it is the responsibility of the transmitting program
          to provide them.
          S0 Record  The type of record is 'S0' (0x5330).  The address



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     SREC(4)                UNIX 5.0 (03/21/84)                SREC(4)



                     field is unused and will be filled with zeros
                     (0x0000).  The header information within the data
                     field is divided into the following subfields.

                                  mname      is char[20] and is the
                                             module name.
                                  ver        is char[2] and is the
                                             version number.

                                  rev        is char[2] and is the
                                             revision number.
                                  description is char[0-36] and is a
                                             text comment.

                     Each of the subfields is composed of ASCII bytes
                     whose associated characters, when paired,
                     represent one byte hexadecimal values in the case
                     of the version and revision numbers, or represent
                     the hexadecimal values of the ASCII characters
                     comprising the module name and description.

          S1 Record  The type of record field is 'S1' (0x5331).  The
                     address field is intrepreted as a 2-byte address.
                     The data field is composed of memory loadable
                     data.
          S2 Record  The type of record field is 'S2' (0x5332).  The
                     address field is intrepreted as a 3-byte address.
                     The data field is composed of memory loadable
                     data.

          S3 Record  The type of record field is 'S3' (0x5333).  The
                     address field is intrepreted as a 4-byte address.
                     The data field is composed of memory loadable
                     data.
          S5 Record  The type of record field is 'S5' (0x5335).  The
                     address field is intrepreted as a 2-byte value
                     and contains the count of S1, S2, and S3 records
                     previously transmitted.  There is no data field.

          S7 Record  The type of record field is 'S7' (0x5337).  The
                     address field contains the starting execution
                     address and is intrepreted as  4-byte address.
                     There is no data field.
          S8 Record  The type of record field is 'S8' (0x5338).  The
                     address field contains the starting execution
                     address and is intrepreted as  3-byte address.
                     There is no data field.

          S9 Record  The type of record field is 'S9' (0x5339).  The
                     address field contains the starting execution
                     address and is intrepreted as  2-byte address.
                     There is no data field.



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     SREC(4)                UNIX 5.0 (03/21/84)                SREC(4)



     EXAMPLE
          Shown below is a typical S-record format file.

                 S00600004844521B
                 S1130000285F245F2212226A000424290008237C2A
                 S11300100002000800082629001853812341001813
                 S113002041E900084E42234300182342000824A952
                 S107003000144ED492
                 S5030004F8
                 S9030000FC

          The file consists of one S0 record, four S1 records, one S5
          record and an S9 record.

          The S0 record is comprised as follows:

             S0     S-record type S0, indicating it is a header
                    record.
             06     Hexadecimal 06 (decimal 6), indicating that six
                    character pairs (or ASCII bytes) follow.

             00 00  Four character 2-byte address field, zeroes in
                    this example.
             48     ASCII H, D, and R - "HDR".

             1B     The checksum.

          The first S1 record is comprised as follows:
             S1     S-record type S1, indicating it is a data record
                    to be loaded at a 2-byte address.

             13     Hexadecimal 13 (decimal 19), indicating that
                    nineteen character pairs, representing a 2 byte
                    address, 16 bytes of binary data, and a 1 byte
                    checksum, follow.
             00 00  Four character 2-byte address field; hexidecimal
                    address 0x0000, where the data which follows is to
                    be loaded.

             28 5F 24 5F 22 12 22 6A 00 04 24 29 00 08 23 7C Sixteen
                    character pairs representing the actual binary
                    data.
             2A     The checksum.

          The second and third S1 records each contain 0x13 (19)
          character pairs and are ended with checksums of 13 and 52,
          respectively.  The fourth S1 record contains 07 character
          pairs and has a checksum of 92.

          The S5 record is comprised as follows:

             S5     S-record type S5, indicating it is a count record
                    indicating the number of S1 records.


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     SREC(4)                UNIX 5.0 (03/21/84)                SREC(4)



             03     Hexadecimal 03 (decimal 3), indicating that three
                    character pairs follow.

             00 04  Hexadecimal 0004 (decimal 4), indicating that
                    there are four data records previous to this
                    record.
             F8     The checksum.

          The S9 record is comprised as follows:

             S9     S-record type S9, indicating it is a termination
                    record.
             03     Hexadecimal 03 (decimal 3), indicating that three
                    character pairs follow.

             00 00  The address field, hexadecimal 0 (decimal 0)
                    indicating the starting execution address.
             FC     The checksum.





































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A note (or minor nit)-
This is the first time that *I* have ever seen the 78-byte limit on total
record length or 64-byte limit on data length. I wouldn't trust those values.

Note also that the count field can have values in the range of 0x3-0xff
(2 bytes of address + 1 byte checksum = 3, a not very useful record), and
that this is the count of remaining character *PAIRS*, including checksum.

Whenever I write code to convert S-Records, I always assume that a record
can be as long as 514(decimal) characters in length (255 * 2 = 510, plus
4 characters for the type and count fields), plus any terminating character(s).
That is, in establishing an input buffer in C, I would declare it to be
an array of 515 chars, and leave room for the terminating null character.

That should cover it :-)
-- 
Ron Widell, Field Applications Eng.	|UUCP: {...}mcdchg!motmpl!ron
Motorola Semiconductor Products, Inc.,	|Voice:(612)941-6800
9600 W. 76th St., Suite G		| I'm from Silicon Tundra,
Eden Prairie, Mn. 55344 -3718		| what could I know?
-- 
"Ribbit!"         Benoit Archambault                    Universite de Montreal 
  ` /\/@\/@\/\          archamba@ERE.UMontreal.CA       C.P. 6128, Succ. A 
   _\ \ -  / /_                                         Montreal, Quebec 
                                                        H3C 3J6
Newsgroups: comp.sys.m68k