Astrobe Forum

Latest updates and changes: https://oberon-rtk.org/description/changes-2024-05-17/ I have taken a first stab at the RP2040's SPI device. There's a corresponding new example program: https://oberon-rtk.org/examples/spirtc/. It uses the Maxim DS3234 real-time clock as test peripheral. GitHub repo: htt...

I have just encountered this problem again, using Astrobe for Cortex-M0 v9.2, where it is partly fixed, but not for all use cases. Just to document in case someone else runs into this as well, here's the test code. MODULE M; VAR i0: INTEGER; r0: RECORD k, i: INTEGER END; a0: ARRAY 2 OF INTEGER; PROC...

The following test code is distilled from a real use case. This is with Astrobe for Cortex-M0 v9.2. MODULE M; VAR v0: INTEGER; PROCEDURE p0(i0, i1, i2, i3, i4, i5: INTEGER; i6: INTEGER; b7: BOOLEAN); END p0; PROCEDURE p1(i0, i1, i2, i3, i4, i5: INTEGER; b6: BOOLEAN; i7: INTEGER); END p1; PROCEDURE p...

Latest update: https://oberon-rtk.org/description/changes-2024-05-05/ Concepts and test code exploring and evaluating the use of trap exception handlers as means to grant exclusive mutating access to shared data, or other protected functionality or hardware: https://oberon-rtk.org/examples/traphandl...

Oops! Seems I was so impressed by the optimisation that I had blanked out the last part. :)

The ARM Architecture Procedure Call Standard (AAPCS) stipulates that, upon calling a procedure 1) registers r0 to r3, and r12, are "caller saved", ie. the called procedure is free to mutate them. 2) registers r4 to r11 are "callee saved", ie. the called procedure must save and restore these register...

Compiling this exception handler PROCEDURE h[0]; BEGIN SYSTEM.LDREG(4, 13) END h; generates this code PROCEDURE h[0]; BEGIN . 1584 0630H 0B500H push { lr } SYSTEM.LDREG(4, 13) END h; . 1586 0632H 0200DH movs r0,#13 . 1588 0634H 04604H mov r4,r0 . 1590 0636H 0BD00H pop { pc } That is, register r4 is ...

Via a typo I have come across this (Astrobe for Cortex-M0v 9.1): MODULE M; TYPE R = RECORD x: INTEGER; x: INTEGER; y: INTEGER END; PROCEDURE p; VAR r: R; BEGIN r.x := 13; r.y := 17 END p; END M. Looking at the assembly code for 'p': PROCEDURE p; VAR r: R; BEGIN . 24 018H 0B500H push { lr } . 26 01AH...

Latest update and changes: https://oberon-rtk.org/description/changes-2024-04-25/ New library module Alarms. Example programs to evaluate a test module Alarms and the library module Alarms: https://oberon-rtk.org/examples/alarmeval/ and https://oberon-rtk.org/examples/alarmtest/. Example program to ...

Latest update and changes: https://oberon-rtk.org/description/changes-2024-04-16/ New example program to introduce the micro-seconds tasking system, with measurements and evaluations of minimum set-up time and minimum time between consecutive tasks, run from flash memory or SRAM: https://oberon-rtk....