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Posted: 03:50am
18 Jul 2026
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Grogster
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New PM3 all-in-one boards, OPTION RESET PICO COMPUTER 3 command issued at the console, answered Y to the question about "...this will erase everything", waited for it to do its thing, but not getting any HDMI output from the board.

Pressed RESET - no HDMI.
Cycled power - no HDMI.
Console works fine, so I feel I am doing something wrong at my end.

Am I using the most up to date firmware?

Silkscreen says I can use any 2350 FW, but I am wondering if that still means from a certain FW revision number....(and I may not be using it)



Edited 2026-07-18 13:52 by Grogster
Smoke makes things work. When the smoke gets out, it stops!
 
Posted: 03:58am
18 Jul 2026
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Grogster
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ADDITIONAL:

I dug out an earlier PICO COMPUTER 2B, and loaded the same FW onto it, and it restarts and the HDMI works fine on it, so I guess I must be doing something wrong with respect to the setup of the new v3 PCB.

My biggest suspect, is that I am not using the latest or correct FW version.

Can someone either link me to the latest version that DOES work with the PM3, or simply post a ZIP file here with the correct uf2 file in it.

Thanks a bunch.  
 
Posted: 04:31am
18 Jul 2026
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disco4now
Guru


I think you probably need 6.03.00
OPTION RESET PICO COMPUTER 3 possibly looks like it is accepted but probably matches
OPTION RESET PICO COMPUTER in the older firmware.

OPTION RESET LIST should show what is available for the loaded firmware.


  matherp said  The release is now available on Geoff's site
https://geoffg.net/picomite.html
Thanks Geoff
 
Posted: 05:08am
18 Jul 2026
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Grogster
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D'OH!  

Not sure why I did not think of hopping on over to Geoff's site before now.....
It's Saturday, and my brain has taken some time off.    
 
Posted: 05:31am
18 Jul 2026
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Grogster
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OK, have HDMI output now, but no USB devices are detected at all.
USB HUB switch is back in the ENABLE position.

ACTIVE LED starts flickering rapidly after a few minutes - it just gets more and more nuts in terms of the flickering.  2350 chip is cool to the touch, HDMI remains steady.

Perhaps bad SMD around that LED?
I will check.
This is the first board I have programmed out of the set of five, so I will do the others and make a mental note if any of the other boards do it.

USB console has a "> [?7h" prompt, no matter what I type, HDMI output does NOT show this, it just shows the normal "> " prompt - is that normal for this FW?
 
Posted: 05:35am
18 Jul 2026
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Grogster
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U35 - the USB hub chip, is REALLY hot.
I mean SO HOT, you can't touch it for more then a few seconds.

I see the ACTIVE LED is connected to this chip, and none of the USB ports work, so something is wrong with the chip on this board.

You should not be able to fry an egg on the top of the USB hub chip.
 
Posted: 05:45am
18 Jul 2026
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Grogster
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Moved on to another board, and on this board, the HDMI and the USB are working fine, USB things are detected, and U35 is NOT roasting hot.

I'll mark the dud board, and have a look under my microscope down at the workshop and see if I can see anything obvious.
 
Posted: 09:18am
18 Jul 2026
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matherp
Guru

I had one with a similar fault. Swapped the hub chip from an older board and it came to life. Not sure what the issue was, whether they had it backwards or with some pins shorted or just a duff chip.

NOTE: with V6.03.00 the Pico Computer 3 will self configure when loaded onto a blank machine or after OPTION RESET
Edited 2026-07-18 19:19 by matherp
 
Posted: 05:40am
20 Jul 2026
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Grogster
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I now have three fully functional PM3 computer boards, if anyone in New Zealand wants one.
Two are duds.
One has the USB chip that wants to be a toaster, and one where the USB-C console simply isn't there to be talked to.
I'll check both the duds under my microscope at the workshop, when I get a spare few seconds.

But that means I do have TWO units that could go to new homes in Kiwiland.....
 
Posted: 11:22pm
20 Jul 2026
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Grogster
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Both sold.
 


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