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ZSM, also known as Z80ASMUK, is a Z80 assembler for CP/M, that outputs HEX files.

I like so much this assembler, so I have recopiled every ZSM version I could find over the Internet and my own disks.

I have even contributed a bit to ZSM with code of my own, mainly patches.

ZSM image

Additional tools

I have developed some companion tools, in order to have a good native development tool chain for the Z80 assembler programming language under the CP/M operating system:

  • zsmpp: source code preprocessor for the ZSM assembler.
  • bintoasm: converts a binary file into an assembler file for ZSM.
  • hextobin: converts a HEX file into a binary file.
  • hextocom: converts an HEX file into a COM file for CP/M.
  • prl: makes PRL relocatable files from COM files.
  • prntosym: extracts symbols from a PRN file (from ZSM v2.8+) and generates an assembler file for ZSM.
  • rsx: manages RSX files.
  • dump: prints file contents in hexadecimal and ascii format.