Search found 681 matches
- Fri Mar 04, 2022 8:10 am
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
And how does MZ-80 A handle the VRAM conflict?
- Fri Mar 04, 2022 8:09 am
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
So you means when GAL decodes $F000-$F3FF, it generates one cycle /EXWAIT? That's so weird.
- Fri Mar 04, 2022 8:07 am
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
20µs is indeed very short. I'm not sure why the GAL is connected to /EXWAIT as an input or as an output especially for $F000-$F3FF. It remains a mystery for me.
- Thu Mar 03, 2022 10:56 pm
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
Yes but sampling should be done upon $E008.D7 (BLNK pulse) and not upon $E008.D0 (TEMPO pulse) as you seem to suggest to Ben.
- Thu Mar 03, 2022 3:59 pm
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
And I cannot find the link between /WAIT (connected to Z80) and /EXWAIT (connected to GAL) in the MZ-80 A schematics. /WAIT is just connected to Z80 with no pull in sight and I cannot spot /WAIT somewhere else. I suspect the schematics missing that part.
- Thu Mar 03, 2022 3:45 pm
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
MZ-80 K:
MZ-700:
- Thu Mar 03, 2022 3:37 pm
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
Also, I'm surprised : isn't $E008.D0 in input supposed to give use a 32Hz pulse for TEMPO? On MZ-700, D0 is 32Hz pulse and D7 is BLNK pulse.
- Thu Mar 03, 2022 3:27 pm
- Forum: Assembly
- Topic: HBLANK (MZ-80A)
- Replies: 25
- Views: 12546
Re: HBLANK (MZ-80A)
@S_U_C I was vaguely supposing the GAL 82S100N (U40) was setting /WAIT = 0 when BLNK = 1 and /CSD = 0 in a similar fashion as MZ-700 to avoid snow effect when video circuit is reading VRAM. So I thought we could try to access VRAM to sync with the BLNK period and switch the hardware scroll address d...
- Mon Feb 21, 2022 9:40 pm
- Forum: Hardware
- Topic: Correct tape type
- Replies: 12
- Views: 6295
Re: Correct tape type
A little bit off-topic: I read we should avoid C-60 tapes for dataset because the more lengthy you get, the more speed will vary according the position due to mechanic constraints. The best is to take the length the closer to what you need to record for one program (it can be multi data block). Tryi...
- Mon Feb 14, 2022 11:37 pm
- Forum: Hardware
- Topic: Please help me identify this Sharp MZ hardware
- Replies: 3
- Views: 2653
Re: Please help me identify this Sharp MZ hardware
Oh there was a word processor WD-2000 (using a Z8000 processor). I suspect WD-50QI being an interface for a word processor.