Raspberry Pi Pico + ePaper display hat

I have been having a go with these, with the aim of using it to display telemetry without problems of visibility in sunlight. (Yes, we do get some in Northern England!)

It is a neat e paper unit that plugs directly into the Pico (which ARE cheap) BUT the software side is not very easy.

C was not easy to use on it but Python (which I don't know very well) was much more straightforward. It seemed to be much better setup for use with a Raspberry Pi than a Windows machine. That's no surprise really.

LATER EDIT (Aug 2022) : Using Python on the excellent Thonny IDE has given better results running on Windows 11. (C using Visual Studio Code 2019 is still very fiddly.) The problem is that the there are not many Python examples in the Waveshare source so the e paper screen gives the data in a small font with a lot of garbage! Just about usable but can be read in sunlight with reading glasses!

LATER LATER EDIT (Aug 2022) : Spoke too soon! Thonny 4 has stopped working with the following error message. "Unable to connect to COM20: port not found. Process ended with exit code 1." Back to the Arduino I think and it's nice IDE.

I really disliked the way that you have to upload software to the Pico. (You plug it in while pressing a button on the back. Very tedious but I see that people are looking at software solutions.)

So I ended up going back to an Arduino. (As you can see in the photo) You realize how well developed the Arduino IDE is and with all that support from the Community.

It turns out that the e Paper support is  a bit limited too so I think my new Telemetry display will be a little slow in development!

So I think I will have a look at the Pico again when it matures a little.

David

I remember seeing this a while ago, it might be usefull
https://www.youtube.com/watch?v=lqXqavwmACQ

I have just "dusted-off" this project. (Partly inspired by my recent introduction to the RP2040 Zero. Thanks geofrancis & Tim.)

I am pleased to say that the ePaper screen project is going again using the latest version of Micropython and Thonny 4.1.3 running on Windows 11.

By Googling for information, the "Unable to connect to COM20: port not found. Process ended with exit code 1."  error seems to have been a bug which has now just gone away!

David

david f wrote:I have just "dusted-off" this project. (Partly inspired by my recent introduction to the RP2040 Zero. Thanks geofrancis & Tim.)

I am pleased to say that the ePaper screen project is going again using the latest version of Micropython and Thonny 4.1.3 running on Windows 11.

By Googling for information, the "Unable to connect to COM20: port not found. Process ended with exit code 1."  error seems to have been a bug which has now just gone away!

David

the rp-2040 is quite unique in how they load the software, most boards use serial or DFU but these actually show up as a removable usb drive when in bootloader mode and ardino just copies the file to it. You dont have to hold the button and plug them in to flash them, you can just press both buttons with your thumb (flash and reset) then let go of reset before the flash button and it will start it bootloader mode.

I feel your pain guys. I just spent over an hour trying to get a silabs based device to speak to a newly purchased windows micro sized desktop pc. i gave up. there does not appear to be a driver for that device compatible with windows 11. I have never had this level of frustration getting all the different 32bit arm devices working in linux. the plan had always been to get the windows install setup, then turn it into an image, wipe the device, install linux, then make a vm with the original image... but a lot of work for a SINGLE piece of software that doesn't work better in linux.

What si device is it ? USB serial? I just spent a day trying to get ubuntu installed onto a lenovo desktop, but turns out the bios wont look for any UEFI files anywhere other than the default windows directory so nothing works.

geofrancis wrote:What si device is it ? USB serial? I just spent a day trying to get ubuntu installed onto a lenovo desktop, but turns out the bios wont look for any UEFI files anywhere other than the default windows directory so nothing works.

yep, its the usb<->serial chip in one of my new radios, the problem is that there is clashing documentation as to which chip it actually is. two different drivers were installed to cover both possibilities, and one driver refuses to work (apparently not compatible with win 11), and of course it appears that driver is the one i need.

interesting that your bios is set up that way, i have had no problems getting ubuntu installed on the two lenovo laptops i have. I don't know if i will be installing ubuntu or mint on the midget puck, but win 11 is definitely not staying.

I tried the ePaper display (Waveshare Pico ePaper 2.9) this Sunday whilst sailing the Russian Nordenfelt using LoRa on 458Mhz.

Well, it is quite readable in bright sunlight (we had a little!) and the display maintaining the data when turned off is interesting. You can see the Telemetry return of 10 volts battery voltage.

However the readability of the display - font size, in particular could be improved. I  needed my glasses!

I have read somewhere that using different fonts is tricky with ePaper and the Pico? Memory available?





More coding work needed.

David

I shall follow this as I was thinking of swapping to a raspberry pi variant as the Arduino doesnt have enough power and I would like to add more s/w capabilities to my next project (pool-side adjustment via blue-tooth, more s/w configuration, level/depth keeping etc. etc.)