srec_cosmac man page

srec_cosmac — RCA Cosmac Elf file format


This file takes the form of one or more RCA Cosmac Elf monitor commands, also known as the IDIOT/4 monitor. Only the change memory command (!M) is allowed.

The general form of the !M command takes the form

!Maaaa dd ... dd

The !M command writes data byte bytes (represented by character pairs dd) into successive memory locations, started at address aaaa. Spaces between data bytes are ignored.

Using the comma (,) line continuation character resumes from the next address in sequence.

!Maaaa dd ... dd, dd ... dd

Using the semicolon (;) line continuation character takes an address on the next line

!Maaaa dd ... dd; aaaa dd ... dd

It is also possible to have the semicolon immediately after the command.

!M; aaaa dd ... dd

All of these forms may be used in combination.

Size Multiplier

In general, binary data will expand in size by approximately 2.0 times when represented with this format.


Here is an example Cosmac file. It contains the data “Hello, World[rq] to be loaded at address 0x1000.

!M1000 48656C6C6F2C20576F726C640A


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Referenced By

srec_cat(1), srec_input(1).

SRecord Reference Manual