Backplane versions

Arc/RPCs, peripherals, RISCOS operating system & ARM kit eg GP2x, BeagleBoard
ajw99uk
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Joined: Fri Sep 29, 2017 3:00 pm
Location: W Yorks, UK
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Backplane versions

Postby ajw99uk » Mon Dec 18, 2017 3:43 pm

A backplane came up on Ebay last week, titled as fitting RiscPC/A5000. Clearly not a RiscPC b/p, and the motherboard connector was on the front-facing side whereas an A5000 b/p has the motherboard connector on the rear-facing side along with the podule sockets. So I dropped the seller a note suggesting he/she might want to re-label it as fitting Archimedes.

But then I saw this
Image
which clearly shows the motherboard and podule connectors on the same side. Chris's Acorns has an A500 and an A3xx b/p with the connectors where I expected them. So I let the seller know about those.

This has niggled, however, and sitting here I can see into the back of the R140 which happens to have been left out with no podules fitted. This has the "A440 UNIX backplane", podule sockets one side, motherboard connector the other. So I hypothesise ...

    other-side layout for A440/R140 and A3xx
superseded by (marginally more space-efficient?)
    same-side layout for A680, A4x0/1 (plus later R140s based on the /1 model, even though labelled "A440, A410") and A5000

(A540/R2xx machines have a third layout)
Running RISCOS: A5000, A540, R140, RiscPC, RPi B
Running *nix: SGI Fuel & Indigo2, RPi2, x86, amd64, RiscPC, A540, R140