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A comment on 80286 ATX mainboard based on the IBM 5170 AT PC. Parent comment

Re:80286 ATX mainboard based on the IBM 5170 AT PC by rasz on Wednesday November 13, 2024 @04:17PM (#42130084)
286 doesnt want anything, CPU is ram agnostic. Project author didnt want to mess with implementing DRAM controller, not that its difficult. Here a simple 16 bit controller realized with ten 74xx chips https://amigaprj.blogspot.com/2013/05/amiga-fast-ram-expande...
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Re:80286 ATX mainboard based on the IBM 5170 AT PC by moosedev on Wednesday November 13, 2024 @06:59PM (#42131615)
Oh right, I didn’t read far enough to see there’s no DRAM support - very unusual for a 286 system (at least a PC-compatible one). That’s a big tradeoff, indeed. Thanks!
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Re:80286 ATX mainboard based on the IBM 5170 AT PC by rasz on Wednesday November 13, 2024 @08:18PM (#42132147)
I wouldnt call it a tradeoff. Author didnt want to design memory controller, and SRAM gets him effortless 0 wait state access.

Personally Im also a fan of keeping ram oldschool. I even reverse engineered a ram card for a 386 board just last week https://github.com/raszpl/386RC-16

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Re:80286 ATX mainboard based on the IBM 5170 AT PC by moosedev on Thursday November 14, 2024 @07:38AM (#42135637)
The tradeoff would be speed and implementation simplicity against the high cost of SRAM, like you highlighted :)

(Re your 386 RAM board: Nice necroproject!)

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