The 1-Bit Forum — new engine: povver

Re: new engine: povver

null@example.com (Shiru) — Sun, 19 Sep 2021 22:21:27 +0000

A note on this issue regarding to 1tracker. Most engines will survive a quick and dirty fix. You can open a *.1te file with a text editor, find there 'out (#fe),a' line, and add a 'and 16' line just before it. It will work in most cases, although a couple of engines may break. The downside of this fix will be a bit reduced pitch and play speed.

Some engines can have pitch issue corrected, although not all of them - find a definition of 'cpuTime', and subtract 7 from the value. If there was a few 'out (#fe),a' lines, add 'and 16' to each of them, and subtract 7 for each one as well.

This is a temporary solution, as it is uncertain if/when we will be fixing the issue. At least I'll add a note for each engine that is currently not compatible with +3, I guess.

Re: new engine: povver

null@example.com (Shiru) — Sun, 19 Sep 2021 13:06:22 +0000

Wow, that's unexpected. Some of my engines guilty with the same thing, though. Squat, for one. Easy to fix, though, but it'll reduce the internal sample rate a bit.

Re: new engine: povver

null@example.com (utz) — Sat, 18 Sep 2021 21:17:07 +0000

Meh, that's pretty bad news. But great you figured it out, thanks a lot for your efforts!

So basically any engine that doesn't mask bit 3 will be incompatible with the +3. Which is like, most of my engines So I guess you better stick to Shiru's engines for now.

Re: new engine: povver

null@example.com (yottatsa) — Sat, 18 Sep 2021 20:02:35 +0000

So yeah, I added

    and #f7 ;11110111b MIC output makes weird noise on +3

before every time it writes to the port and it now sounds pretty normal (but slow, as I obvs messed up with timings).

Re: new engine: povver

null@example.com (yottatsa) — Sat, 18 Sep 2021 18:50:04 +0000

It feels like I have an idea what is happening with 1bit trackers on +3

The ULA chip uses the same pin (28) for all of the MIC socket, EAR socket and the internal speaker, so bits 3 and 4 of an OUT to Port 0xfe will affect bit 6 as read by an IN from Port 0xfe.

tl;dr on a classic speccy different values on bits 3 and 4 produces 4 different distinct levels. However, 1) MIC and EAR are separate lines on the +3 Amstrad Gate Array.

Bit 6 of Port 0xfe of the +2A/+3 does not show the same dependence on what was written to Port 0xfe as it does on the other machines, and always returns 0 if there is no signal.

2) there is no logic for +3 in fuse, that's why it works there.

Re: new engine: povver

null@example.com (utz) — Fri, 17 Sep 2021 10:19:11 +0000

It's totally unclear to me what's going on here. Let's wait for Noel.

Re: new engine: povver

null@example.com (yottatsa) — Thu, 16 Sep 2021 22:35:58 +0000

Could it be the other way around (twice faster), because 48K plays the tone ~480Hz tone, while +3 plays ~970Hz?

(updated the attach so the pulses are aligned, wonder why there is the step on the 48K one on the bottom in the middle of the pulse)

Re: new engine: povver

null@example.com (utz) — Thu, 16 Sep 2021 22:08:04 +0000

Very odd. This should toggle the border color every scanline, but seems it's actually running much slower?
Admittedly I'm pretty much out of ideas, so let's wait and see if Noel will be kind enought to run some tests.

Re: new engine: povver

null@example.com (yottatsa) — Thu, 16 Sep 2021 21:32:17 +0000

Here the results: a screen capture and a scope.

Re: new engine: povver

null@example.com (utz) — Thu, 16 Sep 2021 20:36:40 +0000

Ah, crap. Here you go.

Re: new engine: povver

null@example.com (yottatsa) — Thu, 16 Sep 2021 20:15:13 +0000

@utz you've missed the attach.

I'll try to involve @noelsretrolab as he probably has plenty of it.

Re: new engine: povver

null@example.com (utz) — Thu, 16 Sep 2021 20:12:58 +0000

Damn. Could you try the attached .tap and post an image of the screen? Probably won't tell us much either, though.
You don't happen to know any other +3 user who could test this on their machine?

Re: new engine: povver

null@example.com (yottatsa) — Thu, 16 Sep 2021 19:11:23 +0000

Sounds exactly the same :< Here's .asm. It still produces extra pulses every 20us like on the pulse.png from the drive.

Re: new engine: povver

null@example.com (utz) — Thu, 16 Sep 2021 16:18:10 +0000

I see. Very strange indeed. Yes, sounds like it's running in contended RAM, but then it seems to run at pretty much the same speed as the 48K version!?! Well, let's first rule out contention issues. Could you export an .asm file from 1tracker, and post it here? (Or, if you want, assemble it yourself at 0xc000 and try it out. 1tracker's asm output works with sjasmplus.)

Also, have you tried with any other engines?

Re: new engine: povver

null@example.com (yottatsa) — Thu, 16 Sep 2021 12:26:56 +0000

Here is how it sounds on +3 and on 48k Issue 2

There are a tap file, a recording, and screenshots from scope.

if you see the attached image (+3 on top and in yellow), it seems like +3 sends extra pulse every time.

P.S.

Shiru wrote:

A guy

A girl ;_;