This format comes from Integrated Device Technology (IDT) System Integration Manager (IDT/sim).
It is almost identical to the Motorola S-Record format, except that most of each record is in binary, and there is no line termination character. The 'S' and tag characters are the same (ascii), however all other bytes are emitted as binary, rather than as a 2-byte hexadecimal ascii encoding.
The orginal Motorola S-Record format.
For a different spin on making S-Record into a more densely packed binary file.
srec_cat version 1.64
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The srec_cat program comes with ABSOLUTELY NO WARRANTY; for details use the 'srec_cat -VERSion License' command. This is free software and you are welcome to redistribute it under certain conditions; for details use the 'srec_cat -VERSion License' command.