Just updated my PicoCalc to a Pico 2W. I could use the loader on pico included by the factory on the same SDCard flashing the appropriate loaders. With the Pico 2W (2350), a number of Pico 2 apps work, like uLisp, microPython, picoLua, and uLisp.
As discussed in this forum, PicoMite_PICORP2350_V6.00.02RC23.uf2 does not load. Would love to stay updated, or any instructions on build changes. I have not yet started building apps for the PicoCalc, but it looks like fun.
– Harald
I’m keeping track of the applications that need extra work to be compatible with uf2loader in a github issue: Applications that need patching · Issue #6 · pelrun/uf2loader · GitHub
Since there is a “almost” there, is there a list of apps that are known to work?
Check this gitbub for a replacment uf2 loader. GitHub - pelrun/uf2loader: Bootloader that loads firmware from PicoCalc's SD card Slot.
Um, I think that since you’re posting in the thread for uf2loader, anyone reading it probably already knows about it. 
The post above yours is literally a link to the apps that don’t work yet, but in summary it’s picomite, zeptoforth and micropython. They’re being fixed.
Also Picoware seems to work, but it won’t save my wifi settings so it’s not that useful. This might be a problem for @jblanked to fix 
Is WebMite going to work on bootloader as well? I want my ntp 
Glad the uf2loader is working for you too. Concerning your WiFi: what version of Picoware are you using, are you using the SD card that came with the PicoCalc, and are you able to connect to the WiFi using Picoware?
I was using picoware 1.3.1 and yes the SD card that came with the picocalc. Since it’s only two day I have the picocalc I’m back to direct webmite to learn basic all over again. I will try again as soon as webmite is supported by bootloader
I could not connect to wifi on picoware and it works on website so for now I’m staying like that. Thanks for what you are doing 
Hi,
When I try version 2.1, I’m only getting a blank screen on my PicoCalc. Any advice on what to try? All original hardware (including SD card). I flash the bootloader_pico.uf2. I have the BOOT2040.uf2 in the root directory and both the pico1-apps and pico2-apps directories in the root dir with some uf2 files in the pico1-apps dir. I tried a flash_nuke.uf2 to clean the flash but it did not help. I also tried a different SD card and I’m holding the F1 key at boot. I get a blank screen regardless of whether I hold F1 (or up arrow) or not. I’m able to flash back to the PicoCalc Bootloader v1.0 and that runs fine. Any suggestions are appreciated. Thanks.
Some generic troubleshooting information is below, but it’s moot because I just checked the release binaries on my unit and they don’t work for me either. So you’re probably not doing anything wrong.
I do know it works when built from my internal dev branch. I’ll sort it out and get fixed release binaries up asap.
The UI should show up no matter what after you flash bootloader_pico.uf2, because there’s no application loaded. So if it’s not then it’s pretty much guaranteed to be a problem with loading BOOT2040.UF2 from the sd card.
Flash_nuke.uf2 isn’t necessary when flashing or updating the bootloader, and won’t make any difference (it doesn’t use a persistent flash filesystem.)
I just tried the release binaries again and they worked. So whatever made it fail for me the first time around was spurious, and the problem must lie somewhere else in your setup.
It makes me come back around to it being an issue with the content of your SD card. First, try another SD card if you can (Sandisk are the gold standard here, random other brands may or may not work but are worth a shot.)
There’s one other tiny possibility that hasn’t seemed to show up yet but might be biting you. What OS are you using and how did you copy BOOT2040.uf2 to the card? Try deleting it and then copying it over again (though that’s probably wishful thinking if it’s doing the undesirable thing.)
(technical details: the bootloader itself doesn’t understand long file names for space reasons. While the 8.3 version of “BOOT2040.uf2” should usually be identical, if the OS decided to set it to “BOOT20~1.UF2” instead then things will break. And the OS won’t necessarily give you any way of knowing it happened.)
Apparently in the windows command prompt, dir /-n will show the short filenames.
The problem seems to be that there are lots of substandard memory cards available on the spot market. These cards will pass tests when using SDIO but fail with higher clock rates using SPI. This can be for any brand / any type. For a personal project, needing a larger number of memory cards, I ran into a problem and after several weeks I accidently found that the cause for failure is that the cards can not handle 500Khz SPI baudrate using softSPI on a Pico, some cards failed already below 20Khz. According to MM.INFO(SPI SPEED) (WebMite 6.00.03) the SD card is clocked at 37.5Mhz which could be excessive for substandard memory cards. For my project I have a simple Pico test rig that I use to validate the cards using hardware SPI up to a maximum of 500Khz. To simplify my problem I bought 96 x 4GB memory cards (Intenso), out of the first 18 there were 8 cards that failed the 20Khz test, interestingly according to the CID (Card IDentification) register a number of memory card manufactures were involved.
Hi,
Thanks for suggestions. I tried a total of five SD cards and found an old Sandisk 128mb card and a Lexar 16gb card (not the one included with the PicoCalc) that work. So it seems to have been a card problem. Strange that the original 32gb Lexar, that works with version 1.0 of the Bootloader, didn’t work.
Thanks for the help. I can work with the 16gb Lexar for now.
Win
I’ve made a new release, with the small UI/keyboard fixes that have been stuck waiting for me to finish the next couple of big features (which aren’t ready yet.)
Since a few people have had SD card woes I’ve also added a small diagnostic tool. It uses the same code as the bootloader to mount the SD card and read the BOOTnnnn.UF2 file, but it just shows the results on the screen. So this should hopefully make it obvious where the problem is. Everything has to show PASS for the bootloader to work.
The list that I asked for was “What apps are known to work?”.
The list that you refer to is the opposite, i.e. a list of apps that dont’t work, and some that seem to work but might still not work. I tried uf2 loader and WebMite, but that just gave me a blank screen, and I had to “flash_nuke.uf2” to start all over with only WebMite which I will continue with a bit longer…
Are these updates to the UF2 that gets flashed to the PICO, the UF2 that lives on the SD card, or both?
Thank you very much for the useful bootloader working with the *.uf2 files without modification! I’m using it with MachiKania:
The bootloader works with the official MachiKania uf2 files (phyllosoma_kb.uf2) for Pico, Pico W, and Pico 2, but not with Pico 2 W. When trying initialization of wifi, the process stops as follows:
This problem can be avoided by using the uf2 file here. To build this uf2 file, pico-sdk ver 2.2.0 with mbedtls ver 2.28.8 was used.
I did some research into Micropython. Unfortunately, the pico-sdk is set to 2.1.1 in the latest/most-updated branch and I don’t see any pull requests/issues asking to bump it to 2.2.0.
Micropython doesn’t build successfully under 2.2.0, it needs a bunch of work upstream to fix that. Luckily it’s not strictly necessary to get things working, adding an enable_interrupts(); call at the start of main is all that is actually needed.
My problem currently is that the build process for the existing composite uf2’s hasn’t been well documented, so it’s not been straightforward figuring out how to rebuild them. (this is why we have makefiles, folks!)
