pdp10-its-disassembler icon indicating copy to clipboard operation
pdp10-its-disassembler copied to clipboard
verified publisher icon larsbrinkhoff

PDP-1 binary formats

Open larsbrinkhoff opened this issue 8 months ago • 2 comments

PDP-1 "read-in" format. Binary words on the tape can be either

  • DIO addr, then data, or
  • JMP addr or HLT.

Block format.

  • DIO addr, DIO count, data, one's complement checksum.
  • Or JMP.

CC @aap

larsbrinkhoff avatar Apr 04 '25 07:04 larsbrinkhoff

CC @Sgeo; would you have any use for reading, writing, converting, or merging PDP-1 binary files?

larsbrinkhoff avatar Jun 01 '25 10:06 larsbrinkhoff

The main thing I would like is a disassembler that easily understands a RIM tape. Reading in a tape into SIMH then stopping it quickly and disassembling the dumped memory is probably not the best approach. I could convert RIM format to a memory dump easily. I assume that block format is a popular second stage after RIM format?

Also, I note that several emulators treat DAC as a valid RIM instruction even though the handbook ignores it, with one emulator having a comment about a Lisp tape wrongly using it.

Sgeo avatar Jun 01 '25 18:06 Sgeo