Programming the RP2040 MCU
To upload a new firmware image on the PR2040 (the “pico” part of “pico-ice”), you need to switch to that RP2040 UF2 bootloader mode instead of the FPGA UF2 mode.
You can do that by connecting a jumper between the BT
pin a Gnd
pin, then press the RESET
button:
-
Connect the
USB_BOOT
pin to ground. For instance with a pair of tweezers, a jumper, or an uncoated paper clip. -
Press and release the “RESET” button. The RP2040 now bypasses its firmware, and runs the RP2040 factory bootloader (from internal ROM) instead.
-
Disconnect the
USB_BOOT
pin from ground. -
Look for an USB drive named
RPI-RP2
and mount it, open it, and check that there are only 2 files in it:INFO.HTML
andINFO_UF2.TXT
. If you also have anCURRENT.UF2
, this means you found the FPGA flashing interface, and need to retry steps 1 and 2. -
Copy the
.uf2
firmware file onto the USB drive. -
Eject the USB drive. At this step, the firmware should be uploaded and running.
Troubleshooting
RPI-RP2
is still visible after step 6
This means the device remained in “bootloader” mode. One thing to check is that the USB_BOOT
pin (marked BT
on the board) is not connected to anything anymore, then try to reset the board.