I think this might be a similar issue to trying to get MicroPython running from partitions - viewtopic.php?t=387146 - and particularly - viewtopic.php?t=387430
What happens is the Address Translation which allows the A or B partition to run precludes access to anything beyond the address that the partition has been mapped to, and that includes any file system.
Writing using the Pico SDK functions side-steps the issue but there is no equivalent for reading and a direct read does not work. It is however possible to read via some other address, bypassing the address translation, detailed in the second link above.
What happens is the Address Translation which allows the A or B partition to run precludes access to anything beyond the address that the partition has been mapped to, and that includes any file system.
Writing using the Pico SDK functions side-steps the issue but there is no equivalent for reading and a direct read does not work. It is however possible to read via some other address, bypassing the address translation, detailed in the second link above.
Statistics: Posted by hippy — Mon Sep 01, 2025 12:25 pm