Search found 140 matches

by olofsen
Thu Jun 14, 2018 9:39 pm
Forum: ZX BASIC
Topic: Let's calculate! - renewed arithmetic routines
Replies: 30
Views: 2249

Re: Let's calculate! - renewed arithmetic routines

Edit: (*): the ROM subroutine "03A8 NAME" can be used scan/evaluate such a complex string .... Yes, I left it in place at the beginning of LOAD and SAVE. However, the resulting string can only have A-Z. That is because the ZX81 character to ASCII conversion just adds $1B, otherwise it takes too muc...
by olofsen
Wed Jun 13, 2018 11:24 pm
Forum: ZX BASIC
Topic: Let's calculate! - renewed arithmetic routines
Replies: 30
Views: 2249

Re: Let's calculate! - renewed arithmetic routines

The attached version is Zsolt's latest, with a first try to make the BASIC LOAD and SAVE commands work using USB, even in compatibility mode. In the filename, only A-Z are allowed, and .P is added automatically.
by olofsen
Mon Jun 11, 2018 5:54 pm
Forum: ZX BASIC
Topic: Let's calculate! - renewed arithmetic routines
Replies: 30
Views: 2249

Re: Let's calculate! - renewed arithmetic routines

While the NMI routine is shorter and faster, NMI-CONT is (three bytes) longer and also slower. I guess it will be hard for the ZXmaster to check for the number of T states taken by the original or modified NMI-CONT...
by olofsen
Sun Jun 10, 2018 11:10 am
Forum: ZX BASIC
Topic: Let's calculate! - renewed arithmetic routines
Replies: 30
Views: 2249

Re: Let's calculate! - renewed arithmetic routines

Siggi: does the attached version work? It has the original NMI routine (so it is a little slower), and the change to detect NMIs on the ZXmore.
by olofsen
Sun Jun 10, 2018 9:29 am
Forum: ZX BASIC
Topic: Let's calculate! - renewed arithmetic routines
Replies: 30
Views: 2249

Re: Let's calculate! - renewed arithmetic routines

The LD HL,($400C) in the NMI routine is three bytes earlier, at $0071, so that there is no display. But DS-L perhaps still works before going to compatibility mode?
by olofsen
Thu May 31, 2018 7:38 am
Forum: Software
Topic: Interrupts on ZX81
Replies: 7
Views: 697

Re: Interrupts on ZX81

Another idea could be to use BUSREQ, because it is not used. It may be used by another machine to alter ZX81's memory, so that it thinks a key is pressed (I'm not sure if this causes good or bad weather ;)).
by olofsen
Sat Apr 28, 2018 10:55 am
Forum: Hardware
Topic: ZXPAND and Lambda 8300?
Replies: 28
Views: 4256

Re: ZXPAND and Lambda 8300?

Perhaps it is the INT routine? The routine in the ZX81 compatible Lambda ROM is I think slightly different from the normal ZX81 INT routine which the ZXpand is using?
by olofsen
Wed Mar 14, 2018 5:23 pm
Forum: ZX Spectrum Lounge
Topic: Sinclair Zx Spectrum: absolutely better ...
Replies: 3
Views: 418

Re: Sinclair Zx Spectrum: absolutely better ...

Hi, thank you for this great reading! But, perhaps the Science of Cambridge is best - it is the fastest with lots of RAM, has the best BASIC, and the best colour graphics :)
by olofsen
Tue Jan 02, 2018 9:32 pm
Forum: Development
Topic: ZXMore development thread
Replies: 7
Views: 527

Re: ZXMore development thread

Sure!
by olofsen
Sun Dec 24, 2017 7:27 pm
Forum: Sinclair Misc
Topic: Happy Christmas
Replies: 10
Views: 864

Re: Happy Christmas

Merry Christmas everyone!