search

schlae / snark-barker

A 100% compatible replica of the famed SB 1.0 sound card
651 stars 45 forks source link

sbdiag: CMS tests don't always generate a sine wave #8

Closed schlae closed 2 years ago

schlae commented 2 years ago

Most likely because the tests fail to initialize all the required registers. Running another CMS-supporting program first and then running sbdiag works.

clausecker commented 2 years ago

It was suggested to me that this could also be the result of back to back register writes. While the card already has a flip flop to slow down access to the SAA1099 chips, maybe that is insufficient when having a fast ISA bus. Perhaps some dummy port reads can be inserted to slow down the register access.

clausecker commented 2 years ago

It was suggested that turning off the noise generators before playing a sound might solve the problem.

Testing on my machine, this seems to fix playback of the sine wave.