The first board of a new chip series is always the toughest because we have to figure out all the gotchas and testing techniques. Like, we’re pretty good at spinning RP2040 and ESP32 boards up at this point, but this new iMX RT1011 board requires different tools and tricks.

One thing we like is there’s a built in ROM bootloader with cross-platform USB loader tool that we can run to upload our second-stage TinyUF2 loader. (https://learn.adafruit.com/installing-the-uf2-bootloader-on-nxp-imx-rt10xx-microcontrollers)

Here we’ve successfully made a full tester for our Metro M7 with WiFi – it enters the ROM loader by toggling the bootmode jumpers, uploads TinyUF2 binary, launches UF2, installs a USB-to-UART converter (https://github.com/adafruit/tinyuf2/tree/master/ports/mimxrt10xx/apps/esp32programmer), programs the ESP32 with WiFi NINA firmware (https://github.com/adafruit/nina-fw), then re-loads test firmware that checks all the GPIO connections and swirls a NeoPixel. All in 25 seconds! – video.