The ZIP file contains:
- the TB1 source code (specific to the HXA assembler, also available on GitHub). As written this version is targeted to Seth Morabito's Symon NMOS 6502 simulator (also available on GitHub), but that can be easily changed if desired
- a file defining equates for the MOS 6551 ACIA, which is emulated by Symon
- a 16K ROM image of TB1 suitable for loading into Symon.