Software development

Since the P1 computer is not working yet, I prepare software on my Macbook and transfer it to the P1 via the cassette tape interface.

For writing programs I use BBedit. I created a language module file for syntax highlighting.

To assemble the program to binary code I of course use my assembler.

To test programs I use the WinArcadia emulator. It has a mode for the Central Data computer, and that is a very convenient and quick way to test programs. WinArcadia expects to binaries in the Absolute Object Format (see Signetics Applications Memo SS51 for details). To convert the bin-file that the assembler produces to AOF I wrote a small Perl utility called bin2aof.

The P1 computer at the moment only has a cassette tape interface. The only way for me to transfer programs to it, is to convert them to audio, connect the headphone output of my Macbook to the cassette tape input of the P1, and play the audio. The L)oad command of the monitor will take care of loading the program into memory. It is slow, but it works well and turned out to be quite dependable. Conversion is done using a small Perl utility called bin2wav. It uses to raw audio files: one for a bit 0, and one for a bit 1. Bin2wav uses ffmpeg to convert the raw audio to WAV format.

To facilitate matters, a small shell script make2650 will assemble a file and convert it to AOF and WAV in one go.

To convert binary files obtained from the internet I achieved excellent results using the DASMx disassembler from Conquest Consultants. I use a script that invokes sed to replace the symbolic names created by DASMx to something more meaningful.

This page is part of my P1 restoration website.

Eelco Vriezekolk.
Questions or remarks? Send me an email on eelco[at-sign]ztpe[little dot]nl