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Information Only ; Acorn Atom kit https://www.ebay.com/itm/Acorn-Atom-Homebrew-IC-Kit-/152817148043 Cost :$14 about £11 which is reasoable. Obviously you'll need to buy all the smaller ICs and bits and bobs elsewhere...but it's a start. And : Dragon 32 /Tandy Color Computer https://www.ebay.com/itm...

For anyone interested in building their own 'Super' Atom As designed by Martin A.. >>.I've done some rough costing Prices sourced from eBay.com W65C02P-10 (10Mhz)..................... $2.50 each 82C55 PIO.................................. $1.05 each 6847 VDP....................................$3.50...

74AHC is pretty quick 9ns for the 08 and 11.5 for the 138. The real holdup is the time it takes the VDG to release the address bus to the video memory. Maybe if I were doing a re-design I'd use dual port memory there. Vram access time would them be the same as the rom. And allow room to run a coupl...

I've got some EPM7032SLC44-10 & EPM7064SLC44-10 (fixed 10ns propagation time, 32 I/O lines) CPLDs... these might replace your rather slow 74xx stuff..

I'll have a rummage around and see what I can find : W65C02S-14 CPU.....................................W65C02Pxx 6MhZ or better OK ?? 39SF010A-70 128k Flash ROM ....................W27C010-7, 27C1001-7 OK ?? AS6C62256-55 32k Static RAM ....................Don't think I have any 55ns SRAMs only 15ns...

Hi.

If you post a Bill Of Materials (BOM) list I'll see if I have any of the ICs laid around and I can send some to Dave.. Thus saving you from buying stuff unnecessarily .

I didn't think you could push a 6847 to 6MHz.. as they're effectively multiplexed with CPU and only rated at 1MHz ?? On 6809 systems they are also tied to a 74LS783 Chip.

The ZX next Project https://www.kickstarter.com/projects/1835143999/zx-spectrum-next/updates Now that the ZX Next project has raided more than £723,000 perhaps they should consider investing some of that Money into designing some New 'Real' ZX Spectrum Chips. Namely a ZX spectrum Super ULA givivng ...

Having had a quick and very brief scan through the kick-starter page , I didn't see a price for the finished item, or it may be my dyslexic eyeballs didn't see it ? :) Why Not Design & Make a ‘New’ ZX Spectrum Super ULA ?? I was recently discussing the pros-and-cons of making a ASIC (application...