Search found 5104 matches

by 1024MAK
Sat Mar 16, 2024 2:40 pm
Forum: Hardware
Topic: Atari joystick without ZXpand+
Replies: 33
Views: 1082

Re: Atari joystick without ZXpand+

kmurta wrote: Sat Mar 16, 2024 1:47 pm The Brazilian clones TK82/TK83/TK85 had a joystick input using this scheme. Line A12 is common for keys 6, 7, 8, 0 and line A11 is common for key 5.

The Atari joystick needs to be modified to work in this scheme.
Thank you. That's what I thought.

Mark
by 1024MAK
Sat Mar 16, 2024 10:58 am
Forum: Hardware
Topic: Atari joystick without ZXpand+
Replies: 33
Views: 1082

Re: Atari joystick without ZXpand+

Spinnetti wrote: Sat Mar 16, 2024 3:10 am back in 82, I simply cut a hole in the case, put in a joystick port, and hardwired it to the arrow keys... pretty simple....
Ahh, but number 5 key adds complexity. How did you handle "5" being on a separate half row (and hence using a different "common" line to the rest of the keys)?

Mark
by 1024MAK
Fri Mar 15, 2024 10:31 pm
Forum: Software
Topic: ZXpand+ JOYCFG.TXT file
Replies: 7
Views: 432

Re: ZXpand+ JOYCFG.TXT file

There is most definitely a help or example file somewhere, I've seen it. I just can't remember where...

Mark
by 1024MAK
Fri Mar 15, 2024 9:20 pm
Forum: Software
Topic: ZXpand+ JOYCFG.TXT file
Replies: 7
Views: 432

Re: ZXpand+ JOYCFG.TXT file

ZXpand Commander is a file manager/menu/loader program. See this topic... ;-)

Mark
by 1024MAK
Fri Mar 15, 2024 9:16 pm
Forum: Hardware
Topic: ZX Spectrum Issue 6a short
Replies: 17
Views: 495

Re: ZX Spectrum Issue 6a short

The ULA only runs off the +5V. And indeed, the actual supply to the core goes via resistor R34 to pin 13. The ULA has no direct connections to the -5V or +12V supplies. ULA pin 14 just supplies the peripheral interface circuitry. The normal cause of problems with the -5V or +12V supplies, TR4 cookin...
by 1024MAK
Fri Mar 15, 2024 8:43 pm
Forum: Hardware
Topic: Spectrum modded / composite question
Replies: 19
Views: 722

Re: Spectrum modded / composite question

Well, with only seven 4116 DRAM chips fitted, it will do something, but no, it will not run BASIC.

The ULA should however produce a picture. What you get depends on which chip is missing. The effect being different depending on which one it is that is missing.

Mark
by 1024MAK
Fri Mar 15, 2024 1:37 pm
Forum: Hardware
Topic: Atari joystick without ZXpand+
Replies: 33
Views: 1082

Re: Atari joystick without ZXpand+

BASIC always uses its own ROM routines to read the keyboard. At the lowest level, this is the Z80 processor using the Z80 machine code IN instruction. Each keyboard half row has its own I/O address. The data returned is one byte, but only five bits are keyboard data. Hence it takes eight IN instruct...
by 1024MAK
Thu Mar 14, 2024 5:04 pm
Forum: Hardware
Topic: Atari joystick without ZXpand+
Replies: 33
Views: 1082

Re: Atari joystick without ZXpand+

I was looking at the schematic and wondering how external keyboards work via the edge connector if there is no access to the five KBD lines that go to the ULA. Is the ROM checking for keypresses? I haven't yet tripped over how this actually works yet. That's an entirely new subject... The simple an...
by 1024MAK
Thu Mar 14, 2024 4:56 pm
Forum: Hardware
Topic: Atari joystick without ZXpand+
Replies: 33
Views: 1082

Re: Atari joystick without ZXpand+

Moggy wrote: Thu Mar 14, 2024 4:36 pm I do Have a Kempston but this I seem to remember, unlike what Mark describes, has the extra tangs as used on a Spectrum interface.
As far as I am aware, all the later Kempston versions did have the longer ZX Spectrum edge-connector sockets.

Mark
by 1024MAK
Thu Mar 14, 2024 4:53 pm
Forum: Hardware
Topic: Atari joystick without ZXpand+
Replies: 33
Views: 1082

Re: Atari joystick without ZXpand+

msknight wrote: Thu Mar 14, 2024 4:45 pm I had read that, but Kelly's, "last active" came up with just a dash, so I concluded hadn't been around for a while.
Still active, has visited this week.

Mark