Search found 189 matches

by olofsen
Thu Sep 28, 2023 9:18 pm
Forum: Development
Topic: Detecting if in FAST mode?
Replies: 2
Views: 4673

Re: Detecting if in FAST mode?

The NMI routine increments the alternative A register. The SLOW/FAST routine starts the NMI generator, and tests within a time frame if this register is incremented. With the ZX81 ROM in the ZX80, this does not happen. If bit 6 of CDFLAG indicates a change to SLOW, this test will indicate if SLOW is...
by olofsen
Sat Aug 26, 2023 11:14 pm
Forum: Emulators
Topic: sz81 emulator
Replies: 49
Views: 42040

Re: sz81 emulator

Thank you for writing about the issue with rezurrection. I seem to remember trying it some years ago and that it worked correctly, so possibly some later improvement introduced the issue. I think it is still unknown how the ULA works exactly, but if something works on a real ZX81 it should work on a...
by olofsen
Thu Apr 27, 2023 2:29 pm
Forum: Emulators
Topic: sz81 emulator
Replies: 49
Views: 42040

Re: sz81 emulator

@Moggy: it seems that sz81 hangs with commander versions > 1.7; the joystick (which is not supported) initialization seems to result in a ZXpand read from an unopened file. Now this can be prevented in the ZXpand emulation or the joystick initialization needs a modification. For now, I've created a ...
by olofsen
Mon Apr 24, 2023 11:51 pm
Forum: Emulators
Topic: sz81 emulator
Replies: 49
Views: 42040

Re: sz81 emulator

Hello Greg, under Linux, I have to have upper case names of files and directories, and then the commander does open a subdirectory. I'm not sure how that might translate to Win 7...
by olofsen
Fri Apr 21, 2023 7:14 pm
Forum: Emulators
Topic: Best Mac emulator?
Replies: 15
Views: 5276

Re: Best Mac emulator?

I had to tweak the Makefile.OSX as well to get it to build properly on M1: Change: CFLAGS+=-mmacosx-version-min=10.6 -arch i386 -arch x86_64 to CFLAGS+=-mmacosx-version-min=13.2 and Change: LDFLAGS=-mmacosx-version-min=10.6 -arch i386 -arch x86_64 to LDFLAGS=-mmacosx-version-min=13.2 Also, replace ...
by olofsen
Fri Jul 01, 2022 5:25 pm
Forum: Development
Topic: Decimal to Floating Point
Replies: 11
Views: 3351

Re: Decimal to Floating Point

Code: Select all

RST 18H
or

Code: Select all

LD A,(HL)
before calling DEC2FP may help :)
by olofsen
Sat Jun 18, 2022 2:35 pm
Forum: Emulators
Topic: ZX81 emulator "command-line edition"
Replies: 14
Views: 20125

Re: ZX81 emulator "command-line edition"

The particular page has been moved to https://www.weggetjes.nl/sg/zx81ce.html
Some links on that page still need to be updated.
by olofsen
Sat Apr 30, 2022 7:42 pm
Forum: Emulators
Topic: JSzeddy Down?
Replies: 6
Views: 2609

Re: JSzeddy Down?

It is currently available at https://weggetjes.nl/jszeddy/jszeddy.html
by olofsen
Sun Sep 26, 2021 10:14 am
Forum: Emulators
Topic: SZ81 compiled for intel Mac OS-X
Replies: 39
Views: 22531

Re: SZ81 compiled for intel Mac OS-X

Normally the path to the data is determined at compile time. When run from the command line, sz81 shows "PACKAGE_DATA_DIR". Perhaps this helps in determining the directory where sz81 expects it to be installed/run from.
by olofsen
Tue Jul 27, 2021 6:54 pm
Forum: Emulators
Topic: EightyOne Test Build
Replies: 18
Views: 6478

Re: EightyOne Test Build

sz81's version with "exploratory features" at http://rullf2.xs4all.nl/sz81/ renders sound with code from the "Unreal Speccy" project (following a recommendation by Yerzmyey; a current link is the first one in https://forum.tlienhard.com/phpBB3/view ... 958#p49958).