which basic rom is needed?
I have discussed this with Philips [3] a few years ago, and they were open to sharing it, but I could not find a contact at Microsoft.
[1] https://archive.org/details/20230420_20230420_1351
[2] https://www.retrocomputing.nl/p2000-basic-cartridge/
[3] https://github.com/philips-software
Edit: for reference, the startup screen shows
PHILIPS CASSETTE BASIC
Versie 1.1 NL
14966 bytes vrijI've looked into building my own BASIC implementation and got quite far with that. Unfortunately, most games that were written back then rely on timing that is near impossible to recreate at that level. Emulating cycle exact Z80 behavior and then having the original BASIC routines on top of that is a far easier route.