Motorola M68EVB912B32, User Manual

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S-RECORD FORMAT
68EVB912B32UM/D A-4
The next 16 character pairs are the ASCII bytes of the actual program code/data. In this
assembly language example, the hexadecimal opcodes of the program are written in sequence in
the code/data fields of the S1 records:
Opcode Instruction
28 5F BHCC $0161
24 5F BCC $0163
22 12 BHI $0118
22 6A BHI $0172
00 04 24 BRSET 0,$04,$012F
29 00 BHCS $010D
08 23 7C BRSET 4,$23,$018C
.
.
. (Balance of this code is continued in the
code/data fields of the remaining S1
records, and stored in memory location
0010, etc.)
2A Checksum of the first S1 record.
The second and third S1 code/data records each also contain $13 (19) character pairs and are
ended with checksums 13 and 52, respectively. The fourth S1 code/data record contains 07
character pairs and has a checksum of 92.
The S9 termination record is explained as follows:
S9 S-Record type S9, indicating a termination record.
03 Hexadecimal 03, indicating three character pairs (3 bytes) follow.
00
00 Four-character 2-byte address field, zeroes.
FC Checksum of S9 record.
Each printable character in an S-Record is encoded in hexadecimal (ASCII in this example)
representation of the binary bits which are actually transmitted. For example, the first S1 record
above is sent as shown below.
0101 0011 0011 0001 0011 0001
TYPE
0011 0011 0011 0000 0011 0000 0011 0000 0011 0000 0011 0010 0011 1000 0011 0101 0100 0110 ••• 0011 0010 0100 0001
5 3 3 1 3 1 3 3 0 3 0 3 0 3 0 3 2 3 8 3 5 4 6 ••• 3 2 4 1
S 1 1 3 0 0 0 0 2 8 5 F ••• 2 A
LENGTH ADDRESS CODE/DATA CHECKSUM
3