So I finally caught a pulse, on the same pin. They were just happening quickly and irregularly and so catching on the scope was tough.
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Cool.
Can you also snapshot real INDEX pulse? My scope is out of my scope now 🙂
Hi,
Delay between step pulses on the Amiga was 3ms in custom disk loaders, and a lot more than that (I don’t remember how much exactly) in the OS itself. If you are implementing it, you can stick with 3ms which is the fastest safe step speed and it produces very nice sound 😉
Step pulses themselves were not too wide, the /STEP line was pulled down and up immediately by setting a bit in CIA register so it was probably just for the length of appropriate machine instruction of Motorola 68000 running at ~7MHz.
What exactly are you trying to do here? Perhaps I could help with some info?
Hi Igor,
You’ve selected an odd post to comment on, but this is an odd place, so you are ok. 🙂
The question isn’t what I’m _TRYING_ to do, it’s what I actually _AM_ doing.
https://techtravels.org/wp-content/uploads/pefiles/amiga.html
has a good overview.
I have created a USB external floppy drive controller that reads amiga floppies in and creates .ADF images. There are several different goals.
This post is pretty decent
https://techtravels.org/?p=143
and this post details some of the progress I’ve made
https://techtravels.org/?m=200705
Igor: where were you when I was beating my head against the wall on this? 🙂
I’m not stuck now on any technical problems, just motivation problems. I’ve been putting time etc into it recently, so its coming along
thanks