1024MAK wrote: ↑Thu Aug 15, 2019 9:00 pm
I prefer my internal RAM upgrade detailed here
Hello Bloodnok, welcome
I must admit, I could not resist buying one of your vLA81 Sinclair ZX81 ULA replacements.
When it arrives (and I can find some time) I’ll try hooking it up to the Zeddy that I used in the article on the site I linked to above. I’ll have to reroute one SRAM address line to the vLA81 pin 35 and wire up the remaining SRAM address line to the CPU A14 address line.
Mark
Hi Mark, definitely a neater approach. I've done much the same but didn't cut any tracks. Instead I made a modified socket which did the pin translation needed. Can remove the mod and restore the zeddy to original easily.
Your vLA81 has already shipped (along with the rest) so should reach you in 2-3 weeks (maybe sooner).
mrtinb wrote: ↑Thu Aug 15, 2019 6:51 am
Hi and a warm welcome. Looks like a great product.
Since you, by magic, just create one ULA after the other, how about a ULA for the Lambda 8300? It’s a little different than the ZX81 and has the charset (ROM) build into the ULA.
Just when I thought I had run out of things to do Is there any good source of info on the Lambda? The ROM would probably mean a small FPGA is required but otherwise I'd be interested in taking up the challenge.
Bloodnok wrote: ↑Fri Aug 16, 2019 3:13 am
Just when I thought I had run out of things to do Is there any good source of info on the Lambda? The ROM would probably mean a small FPGA is required but otherwise I'd be interested in taking up the challenge.
Unfortunately the info on Lambda 8300 is quite sparse.
My VLA81 arrived safely to Sweden today. I am VERY happy to report I did not get slammed with the usual customs and VAT. I was a bit worried about that since I thought it was delivered from Germany when I ordered...
Will try to get time to test it this weekend and report back.