Change Note 2025-09-04

Kernel-v4

• Consolidate all kernel modules into module Kernel. The modularity of the kernel architecture is preserved inside the module.
• Update the impacted example programs accordingly.
• Test program K4perf0 for the kernel’s responsiveness.

Library Modules lib/2.1

Exceptions (RP2350)

• Improve setting the priority of interrupts and system exceptions.

GPIO (RP2350)

• Better/clearer separation of functionality of the GPIO pins and their pads.
• Basic support for GPIO interrupts. See K4perf0 for a usage example.
• Consistent support for the RP2350A (29 GPIO) and the RP2350B (48 GPIO) via SIO. Procedure Set2 and siblings are replaced by two separate procedures each for the lower and the upper set of GPIOs. Set2 did set both, but taking two corresponding parameters, so one had to be aware of the split anyway, and adjust the SET parameter accordingly. Also, it used two consecutive store operations, so there was not atomicity for the two sets.
• Quite a few procedures and definitions are now deprecated (marked in the module), ie. replaced by new ones, as outlined above.
• SIO operation may be extracted out into a separate module, see draft SIOgpio.

MCU2 (RP2350)

• Additional CONSTs for data watchpoint and trace (DWT), and the debug control block.

Example Program

• K4perf0: test program for the responsiveness of kernel-v4.