Page 2 of 3

Re: UDG 4 ZXpand / ZXblast

Posted: Fri Aug 25, 2017 2:22 pm
by Andy Rea
i have started a new discussion about using the UDG board

viewtopic.php?f=7&t=2533

regards Andy

Re: UDG 4 ZXpand / ZXblast

Posted: Fri Aug 25, 2017 3:00 pm
by Moggy
siggi wrote: Fri Aug 25, 2017 12:57 pm
Moggy wrote: Fri Aug 25, 2017 11:35 am QUOTE.

"Changing the i register takes only 5 bytes so can be poked into a line 1 rem statement so charsets can be used easily from basic also."

This is the bit that leaves me stumped. :oops:
I have created some UDG's but don't know how to display them using basic any chance of a simple example, say a line of "X"'s being turned into a UDG of my choice?
The 5 bytes in M/C are necessary to change the I register to point to another UDG-character set in RAM. You could use standard POKE command to store the UDG pattern there by BASIC.
I have done that also in my UDG game:
viewtopic.php?f=6&t=526&p=4987&hilit=Interc+u#p4987

Regards
Siggi
Thanks Siggi much appreciated. :D

Re: UDG 4 ZXpand / ZXblast

Posted: Sat Aug 26, 2017 5:35 pm
by 1024MAK
Mine arrived today 8-)
IMG_5200.JPG
UDG 4 ZXpand and some 3.5mm mono jack plugs and sockets
(255.52 KiB) Downloaded 538 times
(Along with a few other bits from eBay)

Thank you Andy :D

Mark

Re: UDG 4 ZXpand / ZXblast and any other ZX81

Posted: Wed Aug 30, 2017 4:28 pm
by siggi
Some years ago I also thought about an extension to have UDG on any Zeddy: a 8KByte static ram on a small board inside the ZX81 (within the ROM socket, carrying the RAM and ROM). Nowadays I would use single gates instead of a GAL:

http://forum.tlienhard.com/phpBB3/viewt ... 3857#p3857

Maybe that would also be useful nowadays ...

Siggi

Re: UDG 4 ZXpand / ZXblast

Posted: Wed Aug 30, 2017 4:31 pm
by Andy Rea
ah yes, the internal mod is a little easier.

regards Andy

Re: UDG 4 ZXpand / ZXblast

Posted: Wed Aug 30, 2017 5:00 pm
by Moggy
Andy Rea wrote: Wed Aug 30, 2017 4:31 pm ah yes, the internal mod is a little easier.

regards Andy
But the green board looks nicer. ;) :lol:

Re: UDG 4 ZXpand / ZXblast

Posted: Wed Aug 30, 2017 6:20 pm
by siggi
My 2 boards arrived this day :mrgreen:
Thanks a lot
Siggi

Re: UDG 4 ZXpand / ZXblast

Posted: Wed Aug 30, 2017 10:23 pm
by hsimpson
My UDG board arrived this day, too :D.
Thank You very much.

Re: UDG 4 ZXpand / ZXblast

Posted: Thu Aug 31, 2017 8:26 am
by nollkolltroll
Board received Monday, and I had time to try it out. All works as expected with the ZXpand :D
Will try it with a classic memory expander some time...

Re: UDG 4 ZXpand / ZXblast

Posted: Thu Aug 31, 2017 8:43 am
by Andy Rea
Hi Adam, goid to hear it arrived safely. By classic memory expander you mean the Sinclair 16k ram pack?

Regards Andy