Commstar was a ROM based communication software that came with the Pace RS232 interface. It had a terminal for general RS232 communication and software for accessing Viewdata systems such as Prestel.
The limitations of the Commstar software, and the desire to use more recently developed file transfer protocols (such as XModem-1k, YModem and ZModem) meant that many users chose to use their Amstrad serial interface with third-party software. This included:
- Ansiterm - a fast AMSDOS utility (also known as ANSI.ARC)
- Charley's Comms ROM - sideways ROM capable of 4800 baud terminal emulation
- ZMP - ZModem file transfer under CP/M