[MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

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Dans34
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby Dans34 » Thu Dec 21, 2017 5:13 am

great work in getting this far
:Octane: R12K/400 Octane, 1024MB, 36GB 15K MAX3036NC , MXI

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GRudolf94
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby GRudolf94 » Thu Dec 21, 2017 5:41 am

I've already found a commercial downconverter that would accept input from a separate 12V rail and output 3.3 @ up to 50A, making it isolated from the CPU 3.3 supply :D

Downside is it costs $66 per individual unit, $45 for the thousand.

The 46A requirement is definitely a worst-case scenario, for a dualhead IMPACT setup, 36A should support a single MaxIMPACT (albeit with minimal headroom). I imagine a Solid would draw between 15-20A, but without the TDP for the chips, official specs, or hacking an original PSU to connect an ammeter between the ribbon and PSU, it's impossible to know the draw for sure.

The full game plan for this is:
1) Finish figuring out the full pinout, unless I can prove some pins can be safely omitted
2) See if IMPACT can be safely driven with a hack
3) Sourcing connectors for making conversion harnesses and IMPACT ribbon
4) Making a PCB for the -5V line which modern PSUs don't provide, and also optionally for the IMPACT feed.
5) Figuring out how to make an ATX PSU fit inside the case
6) Publishing the whole finds, and probably releasing the adapter as OpenHardware
7) Perhaps selling the adapter if viable, and if there's enough demand
8) Publishing at least a partial list of recommended PSUs
:Indy: R5000@180MHz, 256MB, XL-24, IndyCam
:Indigo2: R10K@195MHz in broken teal case with broken purple bottom, XZ Graphics, missing: RAM, drives/sleds, case bits, PSU; awaiting completion [ATX PSU CONVERSION IN THE WORKS!]
misc: Some Sun stuff, lots of x86 crap, one MSX and a MSX2+, a ZX Spectrum clone, slotloader 400MHz overclocked to 500MHz! iMac G3

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GRudolf94
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby GRudolf94 » Tue Dec 26, 2017 11:58 am

Well, another snag:
ATX PSUs are 1/2" wider than the stock PSU, and some 3/8" longer than the width of the stock PSU, so it is quite far from fitting. Sourcing a custom form factor PSU (such as from certain IBM, Dell or HP PCs) that complies with the original current demands may be unfeasible.

The connectors for the mainboard are probably common AMP MTA series connectors, but the IMPACT feed flatcable and connector seem to be custom.

These factors would, quite unfortunately, preclude the creation of drop-in, plug and play ATX PSU adaptors. I'm probably gonna modify my ATX PSU to fit inside the bottom housing of the original PSU (which I do have), and I can repurpose the IMPACT connector from that, but that doesn't constitute a solution for people who don't have the PSU, or are not willing/capable of modifying a stock, damaged unit.

If I come up with anything, I'll keep you posted. For now I'll post full modifying instructions when available.
:Indy: R5000@180MHz, 256MB, XL-24, IndyCam
:Indigo2: R10K@195MHz in broken teal case with broken purple bottom, XZ Graphics, missing: RAM, drives/sleds, case bits, PSU; awaiting completion [ATX PSU CONVERSION IN THE WORKS!]
misc: Some Sun stuff, lots of x86 crap, one MSX and a MSX2+, a ZX Spectrum clone, slotloader 400MHz overclocked to 500MHz! iMac G3

kubatyszko
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby kubatyszko » Tue Dec 26, 2017 1:42 pm

I wonder whether assembling a power supply from smaller modules wouldn't be better, thinking of sth like this:

https://www.digikey.com/product-detail/ ... ND/5226421

https://www.digikey.com/product-detail/ ... ND/2203595

** Those are just for reference, there are some modules with multiple voltages etc.

It would not only be expensive but also need some tinkering to synchronize startup, ensure control from the power button etc.

Cheers
Designer of Fuel ATX PSU adapter board : viewtopic.php?f=3&t=16732341
(now ships from USA), In stock!

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GRudolf94
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby GRudolf94 » Tue Dec 26, 2017 2:09 pm

I thought about getting a big 500W-ish 12V PSU and rectifying all the other rails from it, but I think that ought to cost more than getting an actual IMPACT PSU. Ok, it won't be a 23-year old, unreliable PSU, but anyway, it's not cost-effective. Startup sync is not that troublesome, the biggest issue would be getting soft-on/off to work, IMO.

Provided one gets all that to work in a form factor comparable to the stock PSU, it still leaves the connectors issue to be solved. I haven't yet found a part number or connector series that matches the IMPACT ribbon.
:Indy: R5000@180MHz, 256MB, XL-24, IndyCam
:Indigo2: R10K@195MHz in broken teal case with broken purple bottom, XZ Graphics, missing: RAM, drives/sleds, case bits, PSU; awaiting completion [ATX PSU CONVERSION IN THE WORKS!]
misc: Some Sun stuff, lots of x86 crap, one MSX and a MSX2+, a ZX Spectrum clone, slotloader 400MHz overclocked to 500MHz! iMac G3

kubatyszko
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby kubatyszko » Tue Dec 26, 2017 3:56 pm

GRudolf94 wrote:Provided one gets all that to work in a form factor comparable to the stock PSU, it still leaves the connectors issue to be solved. I haven't yet found a part number or connector series that matches the IMPACT ribbon.


Would you or somebody else be able to share close-up pictures of headers and connectors (including IMPACT) and ideally some measurements - pin thickness and pin spacing ?
Designer of Fuel ATX PSU adapter board : viewtopic.php?f=3&t=16732341
(now ships from USA), In stock!

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GRudolf94
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Re: [MAJOR BREAKTHROUGH!] Indigo² PSU Pinouts

Unread postby GRudolf94 » Tue Dec 26, 2017 4:11 pm

I'm currently travelling for the holidays and away from my Indigo2, and I only have a shitty plastic caliper, but I'll try to when I get home, if no one else provides the measurements in the meantime.

Here's all I had on my cellphone, a pic of the IMPACT ribbon label

The matching connector on the backplane has about 6 ~2mm wide pins, can't quite recall
IMG_20171220_232259.jpg
:Indy: R5000@180MHz, 256MB, XL-24, IndyCam
:Indigo2: R10K@195MHz in broken teal case with broken purple bottom, XZ Graphics, missing: RAM, drives/sleds, case bits, PSU; awaiting completion [ATX PSU CONVERSION IN THE WORKS!]
misc: Some Sun stuff, lots of x86 crap, one MSX and a MSX2+, a ZX Spectrum clone, slotloader 400MHz overclocked to 500MHz! iMac G3


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