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OA47

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Joined: 11/04/2012
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Posted: 12:42am 24 Nov 2023

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After a long night programming I made the dumb mistake of thinking if I made this PI Pico VGA run faster everything would get better. So without thinking things through I Optioned the CPU speed to 378000 without saving the program to any external memory and the unit would not boot.
Am I to believe that I have to reload MMBasic and say goodbye to the programming I have done?

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phil99

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Joined: 11/02/2018
Location: Australia
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Posted: 02:53am 24 Nov 2023

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This is grasping at straws but...
First to ensure it isn't a RUN pin issue put a 1k resistor from RUN to 3.3V.
Next perhaps the increased speed is dragging the 3.3V supply too low. Measure it and if less than 3.2V add an external supply.

If they don't help what you need is some way to erase the Options only on a device that isn't running. Tricky!

Provided the options are stored in the RP2040 chip and not in the flash chip, swapping the flash chip with another Pico might work. (Assuming your program is in the flash chip.)
If they are both on the flash this won't work.
Edited 2023-11-24 13:06 by phil99

TassyJim

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Posted: 03:22am 24 Nov 2023

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You might be able to simply load the latest firmware and see if anything remains.
Sometimes, options get reset but programs remain.

If you have to resort to clearing the flash (which is normally the case), I hope you have a good memory.

Jim

VK7JH
MMedit MMBasic Help

phil99

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Posted: 03:42am 24 Nov 2023

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Perhaps it depends on how different the two versions are.
Going from RC16 to RC21 wiped everything. Going from RC20 to RC21 nothing changed.

Edit

Quote If they are both on the flash this won't work.

If the second Pico will run at 378MHz there is a chance it will work.
Edited 2023-11-24 13:57 by phil99

OA47

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Posted: 04:50am 24 Nov 2023

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Working on Phils straw grasping, and the lack of voltage, I disconnected the keyboard and SD card and the unit booted. I then re connected the keyboard and I could list the program (all be it in MODE 2) but the interpreter would not recognise many commands. I could print the mm.ver (5.7.4 IIRC) and then back to black. I tried again without the KB and SD but no go, got a lithium power pack to supply the USB but still no go.

Frustration is setting in. I am not ready to re-load the firmware as yet. Maybe when I am brave enough.

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vegipete

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Joined: 29/01/2013
Location: Canada
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Posted: 06:22am 24 Nov 2023

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Any signs of life when connected only by USB to a terminal program?

Visit Vegipete's *Mite Library for cool programs.

matherp
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Joined: 11/12/2012
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Posted: 07:46am 24 Nov 2023

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Give me an hour or two and I'll try to create some "recovery" firmware. Exactly what version were you running?
Edited 2023-11-24 18:28 by matherp

OA47

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Posted: 07:58pm 24 Nov 2023

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I am sorry Peter as I cannot get the thing to boot again I cannot verify the version.

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phil99

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Posted: 09:41pm 24 Nov 2023

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Vegipete said Any signs of life when connected only by USB to a terminal program?

This is worth a try. The VGA resistors can draw significant current. Unplug the module and just use USB.

One more straw to grasp. Chill the chip. Put thin clingfilm over the module and press an ice cube on the chip before powering up.
Might give you time to read the version if not change the speed.

Edit

OA47 said I could print the mm.ver (5.7.4 IIRC)

Edited 2023-11-25 07:46 by phil99

OA47

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Posted: 09:45pm 24 Nov 2023

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Thanks Phil for the ideas, but I took the plunge and reloaded 5.7.7 and as not hoped there is no sign of the file so I am exercising the grey cells remembering and re entering the program. Lesson again SAVE,SAVE,SAVE

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PhenixRising
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Joined: 07/11/2023
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Posted: 11:27pm 24 Nov 2023

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Aaaaand we couldn't at least wait for a matherp comeback???

Guessing that Pete had already put some effort into this. Who knows if the version number wasn't merely a nice-to-have.

OA47

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Posted: 02:12am 25 Nov 2023

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I could not confirm with Peter which version of MMBasic was loaded and could not check as it would not boot.

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