PIM543 Pico Display and another SPI device at the same time

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1

I am looking for a way how to hook up the PIM543 Pico Display and another SPI device (RC522 RFID reader) simultaneously.

From the PIM543 spec, I understand that SPI0 bus on pins #16/#17/#18/#19 is used to communicate with the display. If I understand correctly, that leaves me with two options:

  1. Put the other SPI device on the SPI0 bus, and use another CSn pin (GP1) to select it:
    reader = MFRC522(spi_id=0,sck=18,miso=16,mosi=19,cs=1,rst=0)
    But I am not sure if putting another device on the same bus (assuming that works) woud not impact the performance of the display. I don’t need frequent display updating, so perhaps it’s ok to put the display and one or more extra devices on the same bus?

  2. Use the SPI1 bus. But there’s a conflict with the Pico SPI1 bus pins and PIM543 RGB LED pins #6/#7/#8 and switch inputs on pins #12/#13/#14/#15. Since I am not mounting the display directly on the Pico, can the RGB LED and switches be initialized to another Pico pins? From what I see, those pins are fixed in this and this source file. So, apparently, I’d need to recompile the display driver to use different pins. Is there any guide available how to do it? Currently I went the easy way and installed the pimoroni-pico firmware, I’m not sure how to hack together my own uf2 file, or maybe there’s a way to replace just the display driver. For the time being, I could go without using the LED or switches. I am guessing that if I decide not to use the LED/switches, I can just leave them hanging, or pull them down, they are not pulled down on the board already.

Please help me to find the best solution.

2

I’ve run dual displays (st7789) on SPI0, one on CE0 and one on CE1.
I’m currently running two Pico Display Pack V2’s (custom setup) with the new (unofficial) st7789 unifying driver.
I was running a Display Pack V2 on CE0 and 240x240 LCD breakout on CE1 with the current official driver.
Does the RFID reader use a display buffer? If no, it will likely work. Can’t hurt to give it a try using CE1