ROM and Z-80 Reference
This page consolidates all of the ROM and Z-80 related areas of the site, in an effort to bring some more organization and order to the chaos.
ROMs Compared / Checksums
These pages will show the checksums of the various ROMs and identify what version / model they correspond to. The pages also include links on how to check your own ROM CRC.
ROMs Disassembled
These pages disassemble the ROMs and attempt to provide detailed information as to what each line does.
Model I Level II ROM
Multi-part disassembly covering the complete address space
Unreleased Frank Durda IV Model III ROM C
NOTE: There are some errors on this page. I recommend looking at the XDROM entry instead.
View DocumentationXDROM – Model 4 ROM C Replacement
Frank Durda’s Model 4 ROM C replacement explained in detail
View DocumentationTRS-80 BASIC Original Source
Bill Gates released the original 1975 source code for BASIC that formed the basis of many BASIC’s including the TRS-80
You can see his release and notes at https://www.gatesnotes.com/microsoft-original-source-code
The you can download the PDF here.
ROM Issues
ROM Programming Reference
Technical references for ROM addresses, entry points, and programming techniques.
Z-80 Processor Reference
Z-80 Technical Information
Comprehensive reference for Z-80 opcodes and undocumented commands
View Z-80 Reference