[Simulavr-devel] [Bug] VCD trace of PINx register not updated when driven from other port/device

[panic]

Hi *,

The PINx register is not correctly updated in the (VCD) traceer, when a
pin is driven *by a different portpin or even another device* (multicore
simulation). It is correctly traced, when the source is a portpin of the
same HWPort.

In the attached example, PB1 is periodically toggled and it is connected
to PD2, thus the PIND register should change. Compile and run the
example like so:

> avr-gcc -g -mmcu=atmega644 -std=gnu11 -O2 -Wall -Wextra -Werror -o main.elf 
> main.c
> ./run_simulator.py

The attached patch fixes this issue by adding an additional member to
Pin, that points to the IOReg<HWPort> owning that Pin. This allows to
report-back/update the tracer when the pin changes. (much like pinOfPort
does)

Patch, minimum working example, and screenshots attached.

Cheers,
panic

0001-fix-trace-of-PINx-register-when-driven-from-another-.patch
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fail.png
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fail.vcd
Description: application/vnd.gtkwave-vcd

main.c
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pass.png
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pass.vcd
Description: application/vnd.gtkwave-vcd

run_simulavr.py
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