Search found 927 matches

by mrtinb
Mon Jun 17, 2019 10:17 pm
Forum: Software
Topic: Memotech Z80 Assembler question
Replies: 26
Views: 1091

Re: Memotech Z80 Assembler question

My understanding of the ZX81 is: Keyboard is never read in FAST mode.

This is no problem in BASIC, because when program gets to INPUT or INKEY$ it switches over, at reads the keyboard.

In machine language in FAST mode, the keyboard is never read, unless you create your own routine for it.
by mrtinb
Mon Jun 17, 2019 4:46 pm
Forum: Emulators
Topic: sz81 emulator
Replies: 8
Views: 340

Re: sz81 emulator

It seems the macOS download only includes the standard version.

Could you kindly include the ZXpand and ZXmore version with the macOS package as well?
by mrtinb
Sun Jun 16, 2019 10:48 pm
Forum: Software
Topic: Memotech Z80 Assembler question
Replies: 26
Views: 1091

Re: Memotech Z80 Assembler question

I've actually tried for weeks to enter FAST mode while auto-inserting lines, because it's still very slow in SLOW mode. However this is much more complicated that I anticipated. Now the keyboard is not read anymore (because keyboard reading is part of SLOW routine). I have tried to add keyboard read...
by mrtinb
Thu Jun 13, 2019 9:41 am
Forum: Hardware
Topic: White screen and no cursor at all
Replies: 38
Views: 1468

Re: White screen and no cursor at all

Great! :)
by mrtinb
Thu Jun 13, 2019 7:05 am
Forum: Development
Topic: New hardware I/O board using Parallax Propeller
Replies: 14
Views: 432

Re: New hardware I/O board using Parallax Propeller

The connector is not made any longer. So we all buy ISA connectors and cut them to the right size.
by mrtinb
Wed Jun 12, 2019 10:58 pm
Forum: Emulators
Topic: sz81 emulator
Replies: 8
Views: 340

Re: sz81 emulator

GCHarder wrote:
Wed Jun 12, 2019 10:09 pm
Besides the standard ZX81 (sz81), it now has support for Chroma, ZXPand (sz81p) and ZX81NU (sz81n), I don't know what sz81m does.
Acording to the manual, I think it's ZXmore.
by mrtinb
Wed Jun 12, 2019 10:39 pm
Forum: Development
Topic: New hardware I/O board using Parallax Propeller
Replies: 14
Views: 432

Re: New hardware I/O board using Parallax Propeller

Seems like someone already made ZX81 VGA output with a Propeller.

http://zx81vga.ws-nbg.de/main.php
by mrtinb
Mon Jun 10, 2019 6:35 pm
Forum: Hardware
Topic: RF modulator schematic?
Replies: 1
Views: 134

RF modulator schematic?

Looks like the RF modulator is a simple circuit. Does anyone have a schematic for it? Will it work without the metal case?
by mrtinb
Sun Jun 02, 2019 5:43 pm
Forum: Hardware
Topic: White screen and no cursor at all
Replies: 38
Views: 1468

Re: White screen and no cursor at all

The only difference in a UK ZX81 and an US TS1000 is the modulator.

The ULA does not care. All is handled in software. The ULAs are equal. One connection on the PCB is open or shorted depending on whether it is sold in UK or US.