This format is used by Ohio Scientific OS65V-compatible loaders. This family of machines includes the OSI C1P, Superboard II, C2, C4, C8, and Challenger III, as well as the UK101, and Elektor Junior.
The file startes with a period '.' (0x2E), to ensure address entry mode. then a 4-digit hex address, followed by a slash '/' (0X2F) to enter the data entry mode. The initial address is always present. There is no need for an additional address record unless there are gaps.
Each data byte is represented as 2 hexadecimal characters, and is separated by a carriage return character (0x0D) (advance address). The final return character may be omitted.
The data is concluded with a period '.' (0x2E) to re-enter address mode. If an address to start execution is specified, then the last 5 bytes are nnnnG where nnnn is the 4-digit execution address, and G is the 'Go' command.
In general, binary data will expand in sized by approximately 3.0 times when represented with this format.
Here is an example ascii-hex file. It contains the data “Hello, World[rq] to be loaded at address 0x1000, with execution at 0x1003. (On a 6502, this is the opcode for indirect jump to 0x2C6F.)
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.