Graphics on Pico Display - Tutorial

I was just about to ask that same question. Downloaded and saved for future use. Thanks Tony and Shoe. Insert thumbs up smiley here. =)

Shoe…I have received an email back from Pimoroni about my problem and they6 say that the reply was delayed due to ā€œworking through a very high volume of support ticketsā€ so they do seem to have an active support department…

Shoe, Thanks for the pointer to the ā€œFlash_Nuke.uf2ā€ download…sounds like a suicide pill for use as as a last resort…scary. But somehow I do not think that that will solve my problem. My ā€œPico Display Packā€ ,which exhibits the problem of a residual sketch still existing in the Display buffer and a new ā€œDemoā€ sketch ā€œunderlayingā€ the residual sketch. The Pico Display Pack is connected to the Pico MCU via the Pimoroni Omnibus Pack. I have swapped Pico’s back and too on the Omnibus and the problem still persists so,… to my mind…the problem lies in the buffer memory of the Pico Display Pack, not the Pico MCU ā€œflashā€ memory. What I think I need is something to ā€œblastā€ just the Display Pack ā€œflash memoryā€ā€¦does that sound logical to you??

I will be ordering one or more of those Captain Resseti reset buttons. I have a button with female jumper leads on it that I can use with my Omnibus for now. No having to unplug the USB.
I’m no expert on this, but my guess is certain parts of the PICO get configured a certain way when you run one file, and some of that doesn’t get undone when you run a second file. Not without a reset. Best guess anyway.

I ā€œthinkā€ the flash_nuke.uf2 just puts it back to the ā€œout of the boxā€ state? Ready for you to decide it you want to go C+, Micro Python, or Circuit Python by flashing a new uf2.
That’s my read on it, I don’t see it doing any harm.

So the Display pack doesn’t have any flash itself, the RAM in the display driver should get wiped when the board is reset (it needs power to hold the data). However, I’ve been doing a bit of graphics work on the Pico Explorer, and occasionally I end up in an odd situation where saving new programs just doesn’t seem to work and it keeps runing the old program. Backing up the programs and nuking the file system seems to undo it.

I’m getting possible ā€˜reliability’ problems with my explorer. I’m using it most of the day and as time goes on I get random pixels, mainly at the bottom but occasionally at the top and Thonny and the Pico stop talking to each other.

I unplug the big end of the USB cable at the PC end. Pulling/pushing the small end in Pico is just asking for trouble.

Yes, I’ve been getting something similar Tony. I’m not sure if this is an issue with MicroPython, the Pico, or the Explorer, but somewhere, something is going wrong.

I bought one the of the Captain Resetti boards exactly because I didn’t want to be putting a lot of wear on the USB port. I’m really surprised the Pico doesn’t come with one, it’s super useful.

I’ve got my Pico attached to a very cheap 3 port USB hub on my desk. I’m just using the middle USB at the moment. I’ve had to unplug and re-plug hundreds of times in the last week so I’ll see how long that middle USB port lasts. My soldering is rubbish right now so won’t be getting a Captain Resetti until much later although I’m thinking of just breaking down a USB data cable and putting a reset switch into that instead.

You can get USB cables with power switches in them, you just have to make sure its a Data cable and not just power.