I am currently using two RFM69HCW transceivers (ISM) for a remote weather station. The current display is a OLED 128x64, but the characters are quite small. So, I decided to try the Pico Display Pack 2.8, 320x240. Plenty of real estate for the numbers now. However, I am a bit vague as to which pins are not being used by the display pack, so I can use them for the transceiver. I need 6 pins for DI0-DI5, plus 5 additional pins for RX, TX, CS, SCK and RST (for xcvr). Are there that many unused pins available in the Display Pack 2? And can the RGB pins be used if necessary.
BTW, the color display is fantastic, but very tight when used on a dual expander board.
You can check the free pins in the schematic from the shop. You can share the RX, TX, SCK pins with the display btw. if you have pullups on your CS lines.
Also, do you really need DI0 - DI5? You should check, since I can operate my RFM69 without any these pins. But this depends of course on the driver you use.
Thank you for the reply. In my case, I am using Packet mode with AES and Sync. So, the DI0-4 pins are used for RSSI, TxReady, RxReady, Data, PacketSent (in no particular order). I may not be using DI5 as I have no use for ClkOut. The libraries I am using are modified from LowPowerLab, as the RadioHead libraries seemed rather broad for my narrow purpose. However, it would be desirable to connect all the pins for more mapping flexibility. The only schematic I found, dated 07/10/2021, is labelled for “Display Pack 2.0” but still shows the LED pins on Pico pins 9-11. Is there a newer schematic?
There is some info here: Pico Display Pack 2.8 info?. According to this post the pins for the LEDs have moved.
If you look at the back of the Display-Pack 2.8, you can see “LED CUT” and some solder traces you can cut. So once you take out your knife you should be able to repurpose those GPIOs.
The product page mentions the new pins used. I’m not sure if it did when I started that thread but it is mentioned now.
Note that the RGB LED is hooked up to different pins on 2.8" (26, 27 and 28) so you may need to adjust for this in your code.
Thank you both for the updated info. I did find the new schematic, which indicates the new LED pin-outs, and cutting. It seems I may have to be creative in selecting pins for the transceiver. Sounds like fun!
If I manage to get this project working with the new display, I may post additional info here, if it may be useful. Have a great day!
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I have two Display Pack 2.8’s wired up side by side on a weather station build. It’s the data display end. It’s been a work in progress for what seems like forever. All was fine with an RP2040, but I had to add 10k pullups to the CS lines to get them to work with an RP2350.
Code runs fine from Thonny, but not as main.py - Support - Pimoroni Buccaneers
Unless I can determine how to use the same SPI pins as the LCD uses, I have discovered there are just not enough free pins to use the RFM69HCW, with DI0-4. Unless someone has some code snippets that have accomplished that (multiplexing?). Or some fresh ideas…
I am working on getting two picos talking to each other, but a problem exists on how to recover the sent message in ‘main()’ without slowing down the interrupt routines. There is a LOT of code to run the transceivers.
The Pico Plus 2 has some extra GPIO on the SP/CE connector. It uses the RP2350B.
Pimoroni Pico Plus 2
8 Pin JST-SH Cable (SP/CE) – JST-SH to DuPont sockets (pimoroni.com)
Or maybe the PGA2350, its also a B. It’s a bit of work wiring it up though.
PGA2350 (pimoroni.com)