Search found 5116 matches

by 1024MAK
Sat Apr 13, 2024 3:21 am
Forum: Hardware
Topic: M1 / printer interface
Replies: 2
Views: 102

Re: M1 / printer interface

The ZX81 uses mode 1 (IM 1) so does not care about what is on the data bus. Hence you don’t need to worry about /M1.

Mark
by 1024MAK
Wed Apr 10, 2024 6:50 pm
Forum: Hardware
Topic: ZX81 blank screen
Replies: 30
Views: 1737

Re: ZX81 blank screen

Lots get caught out by the UK700 producing 12V to 16V when off load, and 10V to 12V when on load.

Good that you are making progress.

Mark
by 1024MAK
Tue Apr 09, 2024 9:38 am
Forum: Welcome Area
Topic: Mandatory intro post / 6502 Z80 content
Replies: 1
Views: 243

Re: Mandatory intro post / 6502 Z80 content

Hello and welcome to our forum reanimate!

:D :D :D

I hope you enjoy this forum :D

Nice set of 1980s computers and extra hardware 8-)

You are welcome to ask questions!

Mark
by 1024MAK
Sat Apr 06, 2024 9:14 am
Forum: Welcome Area
Topic: ZX newbie
Replies: 2
Views: 94

Re: ZX newbie

Hello and welcome to our forum Staffan!

:D :D :D

I hope you enjoy this forum :D

You are welcome to ask questions!

Mark
by 1024MAK
Fri Apr 05, 2024 12:25 am
Forum: Hardware
Topic: Cursor off-screen
Replies: 9
Views: 412

Re: Cursor off-screen

The cursor is not likely to be off-screen, more likely is that the video contrast (voltage) is wrong. Hence the K cursor may be there, just not visible. If the picture size was incorrect, I would expect a rolling image, due to incorrect sync. Keep in mind that the transistor type composite modificat...
by 1024MAK
Thu Apr 04, 2024 5:26 pm
Forum: Hardware
Topic: how to verify if a multiface 1 is working ??
Replies: 16
Views: 1026

Re: how to verify if a multiface 1 is working ??

Ahh, I was going to reply the other day, must have forgotten :oops:

As the Opus also uses it's own ROM, has the previous owner fitted or modified the MF1 board with a switch or some other method to disable/prevent it's ROM and RAM from being paged in?

Mark
by 1024MAK
Thu Apr 04, 2024 5:23 pm
Forum: Welcome Area
Topic: Thanks for letting me join
Replies: 3
Views: 130

Re: Thanks for letting me join

Hello and welcome to our forum Luke!

:D :D :D

I hope you enjoy this forum :D

You are welcome to ask questions!

Mark
by 1024MAK
Tue Apr 02, 2024 5:00 pm
Forum: SALES
Topic: Memotech 16K RAM pack - working. £20 plus p&p
Replies: 8
Views: 456

Re: Memotech 16K RAM pack - working. £20 plus p&p

voorsk wrote: Tue Apr 02, 2024 3:34 pm I tried before, and it didn't complain, altho the message is still in my outbox. I can think of a couple more things to post, just in case. :)
As Moggy says, a PM/DM will sit in your outbox until the recipient reads it. Only then will it move to your sent box.

Mark
by 1024MAK
Sun Mar 31, 2024 11:52 am
Forum: ZX BASIC
Topic: Forcing an NMI or locking the keyboard via poke command
Replies: 1
Views: 278

Re: Forcing an NMI or locking the keyboard via poke command

You can't force a NMI. A NMI is a non-maskable interrupt which is a hardware signal. Machine code can jump to the address where the NMI routine is, but it's not quite the same. Machine code can HALT the processor, just execute the HALT instruction. But this will not do what you want on a ZX81. I pre...
by 1024MAK
Sun Mar 31, 2024 11:38 am
Forum: Hardware
Topic: SOLVED !! opus discovery questions
Replies: 7
Views: 491

Re: opus discovery questions

can a " twisted " cable solve this ? Not with a twisted cable designed for PCs, as it will also twist the motor on line, but the Opus only has a single (common to all drives) motor on signal, as it uses a Shugart interface. Shugart interface Floppy Drive Interface Pin Function 2 /DCD Disk Change De...