Search found 387 matches

by David G
Sun Jan 22, 2023 8:16 pm
Forum: Software
Topic: [Type_ins] Fun Program from EMI cassette tape
Replies: 1
Views: 991

Re: [Type_ins] Fun Program from EMI cassette tape

Aside from the surprising elegant and compact BASIC program, the entire J-card is interesting with many helpful tidbits. Back in the day I might have not even read this card info, but the 8bit Show & Tell has pointed it all out. Good video THORN EMI EMITAPE Computer Cassette C20 Use to record (SAVE)...
by David G
Sun Jan 22, 2023 12:10 am
Forum: Software
Topic: [Type_ins] Fun Program from EMI cassette tape
Replies: 1
Views: 991

[Type_ins] Fun Program from EMI cassette tape

This was included in the EMI brand tape cassette J-card . Probably from early 1982 See the video by 8-Bit Show And Tell: Youtube: The Tiny Type-In Hiding In A 40-Year-Old Blank Computer Cassette 10 PRINT "MOVE THE BLACK SPOT BY PRESSING" 20 PRINT "THE APPROPRIATE ARROWS (KEYS 5,6,8 AND 8)" 30 PRINT ...
by David G
Tue Jan 17, 2023 9:00 pm
Forum: Hardware
Topic: ZX80/ZX81 with a 6502 ...
Replies: 8
Views: 1905

Re: ZX80/ZX81 with a 6502 ...

Paul wrote: Tue Jan 17, 2023 10:56 am
David G wrote: Tue Jan 17, 2023 4:58 am One question, doesn't the 16K RAM PAK have its own refresh circuit?
Please don't abuse this thread
I was replying to this thread which said the Z80 was superior for supporting DRAM refresh. But did the ZX81 make use of that feature? ZX81 did not use DRAM, only the add-on memory packs used DRAM
by David G
Tue Jan 17, 2023 4:58 am
Forum: Hardware
Topic: ZX80/ZX81 with a 6502 ...
Replies: 8
Views: 1905

Re: ZX80/ZX81 with a 6502 ...

Great posts, very interesting information!

One question, doesn't the 16K RAM PAK have its own refresh circuit?
by David G
Tue Jan 17, 2023 4:29 am
Forum: Hardware
Topic: Using standard PC keyboard with ZX81
Replies: 7
Views: 1478

Using standard PC keyboard with ZX81

Has this been discussed before?


Seems like we could use an Arduino or Nano Pi to read a USB/Bluetooth or PS/2 keyboard and generate the correct signals for the 9 pins of the ZX81 keyboard connector. I have sooo many spare keyboards ...
by David G
Wed Jan 11, 2023 6:20 am
Forum: Development
Topic: [Type_ins] The Valley of adventure: Poster Programs 1
Replies: 60
Views: 21490

Re: A 15.999K Adventure game: The Valley of adventure.

Later release: ... - Off screen D_file destruction avoid at the right and the left sides. ... You have a great fix, which I was struggling to implement -- i only had IF G$="4" THEN GOTO 2050. Your change also fix the diagonal movements (1 and 7 keys) 2065 IF (G$="1" OR G$="4" OR G$="7") AND PEEK (W...
by David G
Wed Jan 11, 2023 6:04 am
Forum: Development
Topic: [Type_ins] The Valley of adventure: Poster Programs 1
Replies: 60
Views: 21490

Re: A 15.999K Adventure game: The Valley of adventure.

R-2 uses extra bytes and time might as well use 21. 23 would work if there's a POKE 16418,0 somewhere, I'll have to check. Ah, I see you are correct: 250 POKE 16418,0 This is DF_SZ : The number of lines (including one blank line) in the lower part of the screen. Changing it to zero allows one to PR...
by David G
Tue Jan 10, 2023 7:20 am
Forum: Development
Topic: [Type_ins] The Valley of adventure: Poster Programs 1
Replies: 60
Views: 21490

Re: A 15.999K Adventure game: The Valley of adventure.

GCHarder wrote: Thu Jan 05, 2023 9:30 pmI'd recommend replacing the "/" in names with CHR 2, the NE block pixel, looks better IMO.
Good idea. As an solution to the problem of "ZX81-has-no-apostraphe", I think you are right: CHR$ 2 generally looks better than the slash
using Slash for an apostrophe
using Slash for an apostrophe
using CHR$ 2 for an apostrophe
using CHR$ 2 for an apostrophe
by David G
Tue Jan 10, 2023 6:57 am
Forum: Development
Topic: [Type_ins] The Valley of adventure: Poster Programs 1
Replies: 60
Views: 21490

Re: A 15.999K Adventure game: The Valley of adventure.

typo: 1570 PRINT "A PRECIOUS STONE"; It works ... however, this matches the Poster Program listing. Either way works. 1570 PRINT "A PRECIOUS STONE.." Line 1570.png And this typo in my matching-the-poster BASIC listing. I have updated my previous post : 1508 POKE M+V,52 52 is the player symbol (CHR 5...
by David G
Tue Jan 10, 2023 5:41 am
Forum: Development
Topic: [Type_ins] The Valley of adventure: Poster Programs 1
Replies: 60
Views: 21490

Re: A 15.999K Adventure game: The Valley of adventure.

XavSnap wrote: Mon Jan 09, 2023 3:34 am Later release

Code: Select all

 537 PRINT AT R,K;G$
matches the Poster Program listing, but results in error 5/537 (No more room on the screen")

R is the constant for 23, which is not valid for a PRINT AT statement. This modification appears to work:

Code: Select all

 537 PRINT AT R-2,K;G$