Change Note 2025-08-11

Kernels

New Kernel-v4

• Based on kernel-v3, adding background tasks.
• Plus periodic tick events, based on sys tick interrupt.
• Plus semaphores, and kernel alarms for micro-seconds timing events.
• See Description.
• Example programs K4base, K4sema, and K4alarms for RP2350 (Pico2).

Kernel-v3, Kernel-v3t

• Use correct SYSTEM.EMITH in lieu of SYSTEM.EMIT.
• Clean-up.

Remarks

• Kernel-v3 and kernel-v3t are of exploratory nature, and will not get any more work. They will remain in the repo, but will not appear any more in the docs (website).
• Same for kernel-v2.
• The nomenclature and documentation are a bit all over the map right now, and will be consolidated once the new kernel library modules have reached a more stable structure.
• The code still contains (mostly?) commented out debugging code. To be cleaned up.

Other Library Modules lib/v2.1

Alarms

• Use Alarms.Device for GetTime, not timer number.

MCU2

• Change CPSIE to CPSIE_I, CPSID to CPSID_I (assembly code to modify PRIMASK).
• Add CPSIE_F and CPSID_F to modify FAULTMASK.

Config Files

• Add kernel-v4 config for Pico2.

Example Programs

• K4base: basic test program for kernel-v4 for background tasks.
• K4sema: test the use of semaphores.
• K4alarm: test the use of the kernel alarms.