yamaha_dx97 VS Murphy

I've been writing a lot of 8-bit assembler for the 6303, which is in the same processor family as the CPU in the TRS-80, which the author is writing code for (for this project in case anyone is wondering: https://github.com/ajxs/yamaha_dx97). I ran into the exact same issue. I wrote a MAME driver for the target platform, so I could test my builds on my development machine. Obviously that sped things up a lot. The MAME debugger isn't really a tool for unit testing, and can't really be easily instrumented, but I was able to write a lot of scripts for the debugger which would set up the breakpoints and system memory for an individual 'test'. Not quite unit testing, but as close as I could get cheaply.

I'm super impressed that someone has emulated the CZ-101's sound generation LSI!

Lots of people use MAME as an emulator to help reverse-engineering vintage synthesisers. I only recently discovered this too. Since most 80s synths were built mostly out of 'off the shelf' components, it's not too difficult to build a MAME driver which is capable of running the synth's firmware. The actual sound generation is another story though.

I wrote a MAME driver for the Yamaha DX9 while working on this project: https://github.com/ajxs/yamaha_dx97

I wrote a little bit about the project here in case anyone is interested: https://ajxs.me/blog/Hacking_the_Yamaha_DX9_To_Turn_It_Into_...

Very cool! I've been doing a lot of work reverse-engineering the firmware from Yamaha's 1980s synthesisers[0], all of which feature Hitachi 6303-series processors. The 6303 is Hitachi's second-source implementation of the Motorola 6803 architecture. I'd love to know how these devices were developed. I'm guessing a development platform like this would have been used by Yamaha. If anyone has any more information regarding development targeting the Hitachi 6300 series chips in the 1970s/1980s, I'd love to know!

[0] In case anyone is curious, my latest successful work is hacking the Yamaha DX9 to have the full DX7 feature set: https://github.com/ajxs/yamaha_dx97

If you don't mind swapping some chips, there's a project to bring out the full potential: https://github.com/ajxs/yamaha_dx97

Yeah I sometimes write tests that are separate from external dependencies still, I think the freedom I gained through this attitude is that I don’t stress too much about it, especially in the early stages. This gives me “good enough” coverage most of the time without the sorts of extreme bending over backwards to mock out every little dependency that a purist unit testing approach would entail.

As a side note I really liked using Lettuce when I was working with Django not so much because of the whole “BDD” thing which was lost on me but because of the way they did database fixtures.

I wrote a little automated test runner in PHP that uses the same approach, and later wrote a little test runner in node with the same name (but never implemented database testing in it because I’m not masochistic enough to use asynchronous code to access a database):

https://github.com/iaindooley/murphy