Search found 342 matches

by Nasta
Wed May 08, 2019 7:21 pm
Forum: Hardware
Topic: Issue 8 discussions...
Replies: 143
Views: 18561

Re: Issue 8 discussions...

Level 5 is only unusable in a stock BBQL because : 1) the autovector is unusable in current ROM 2) The hardware has no feature to block a level 2 interrupt, so although you can generate a level 5, it is likely to become a level 7 because of that other IPL line getting toggled by the ZX8302 or even ...
by Nasta
Wed May 08, 2019 7:12 pm
Forum: Hardware
Topic: Issue 8 discussions...
Replies: 143
Views: 18561

Re: Issue 8 discussions...

The J1 DIN41612 connector is implemented, but some signals have been changed. We've converted some to ground, and others to extend the address bus. Also, the 68SEC000 does not implement the 6800-style interrupt system, so we made useful changes there. The only card we're aware of that used the 6800...
by Nasta
Tue May 07, 2019 1:30 pm
Forum: Hardware
Topic: Issue 8 discussions...
Replies: 143
Views: 18561

Re: Issue 8 discussions...

I've got a couple of SCN68681 (DIP40) on the way, so I'll have something to play with meantime :) BTW did you consider priority encoding IPL0/2 & IPL1 interrupt on issue 8? As you may well know level 5 is unuseable (since if level 2 occurs you get level 7). The 3 byte receive buffer of the 6868...
by Nasta
Sun May 05, 2019 12:10 am
Forum: Software & Programming
Topic: My Gold Card is faster than yours! Well nope it doesn't work.
Replies: 10
Views: 1302

Re: My Gold Card is faster than yours! Well nope it doesn't work.

But... The 80P50 uses an external ROM, so if you can find those they are always fun to have. If you can find them! So does the 8049 but then the data on the data bus is latched and with 4 port lines are used to supply an address to the external memory. It is possible to re-create the pins in the ca...
by Nasta
Sat May 04, 2019 11:11 pm
Forum: Software & Programming
Topic: My Gold Card is faster than yours! Well nope it doesn't work.
Replies: 10
Views: 1302

Re: My Gold Card is faster than yours! Well nope it doesn't work.

Also they have added MCS-51 compatibility to the II but not MCS-48 :( I'd have bought it (again) if it supported MCS-48 (like 8049/8749). 8741/42/48/49 have a rather odd way of reading and writing the internal (EP)ROM, which applies a high voltage to multiple pins at the same time, which the TL866 ...
by Nasta
Wed May 01, 2019 2:28 am
Forum: Hardware
Topic: ULTRA GOLD CARD
Replies: 24
Views: 2818

Re: ULTRA GOLD CARD

On no you don't. I get first dibs, because I'm Nasta :) I have to figure out how to feed that many of us :P
by Nasta
Tue Apr 30, 2019 12:09 pm
Forum: Hardware
Topic: ULTRA GOLD CARD
Replies: 24
Views: 2818

Re: ULTRA GOLD CARD

Nasta, many thanks for that interesting history lesson. You remember a lot better than me. Actually, I was surprised how much I did remember, though that post went through about 4 revisions as things came back to me :P Most of the spec and logic was already done on paper but having a tool chain (wh...
by Nasta
Tue Apr 30, 2019 11:51 am
Forum: Hardware
Topic: ULTRA GOLD CARD
Replies: 24
Views: 2818

Re: ULTRA GOLD CARD

I was at one of the Italian 'Garage meetings' at Davide Santachiara's garage when Stuart talked about the Masterpiece Actually I recently watched the video of the meeting as a sort of tribute to Stuart: https://www.youtube.com/watch?v=ftW75wM5fmk . You were so young :-) Oh lord were we all ever you...
by Nasta
Sun Apr 28, 2019 12:41 am
Forum: Hardware
Topic: ULTRA GOLD CARD
Replies: 24
Views: 2818

Re: ULTRA GOLD CARD

As the author of said vaporware, I can only agree. When I did Aurora I hoped it would get the QL out of it's old case but no such luck... If the announcement was about a variant of the GoldFire, then why does it say "Miracle Systems" and not "Nasta"? Are you sure this was not so...
by Nasta
Sun Apr 28, 2019 12:01 am
Forum: Software & Programming
Topic: SCREEN1 = SYSVAR @ JSROM
Replies: 90
Views: 11105

Re: SCREEN1 = SYSVAR @ JSROM

Why not check out Minerva? It's already designed to work with 2 screens and in fact the con driver linkage block can be modified to generate graphics in the second screen - in fact, in theory, anywhere in memory. It's fairly easy to look at the two screens as a larger 512 x 512 bitmap and then use i...