Cannot get MCU connection with simulavr

[andersevenrud]

Hi,

I've set up a fresh instance and want to test out the debugging stack, but can't seem to get a connection to the simulated MCU.

I start the stack with the following:

docker compose \
  --profile mainsail \
  --profile hostmcu \
  -f docker-compose.yaml \
  -f docker-compose.extra.simulavr.yaml \
  up -d

The simulator starts up fine:

simulavr-1  | Starting AVR simulation: machine=atmega644 speed=16000000
simulavr-1  | Serial: port=/opt/printer_data/run/simulavr.tty baud=250000
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 252: MCU register MCUSR not simulated (write 0x00 to register)
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 246: MCU register WDTCSR not simulated (read from register)
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 252: MCU register WDTCSR not simulated (write 0x18 to register)
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 252: MCU register WDTCSR not simulated (write 0x00 to register)
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 252: MCU register WDTCSR not simulated (write 0x18 to register)
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 252: MCU register WDTCSR not simulated (write 0x0d to register)
simulavr-1  | WARNING: file /opt/simulavr/libsim/rwmem.cpp: line 252: MCU register WDTCSR not simulated (write 0x40 to register)

Klippy log says the following:

mcu 'mcu': Wait for identify_response
Traceback (most recent call last):
  File "/opt/klipper/klippy/serialhdl.py", line 75, in _get_identify_data
    params = self.send_with_response(msg, 'identify_response')
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/klipper/klippy/serialhdl.py", line 271, in send_with_response
    return src.get_response([cmd], self.default_cmd_queue)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/klipper/klippy/serialhdl.py", line 331, in get_response
    self.serial.raw_send_wait_ack(cmds[-1], minclock, reqclock,
  File "/opt/klipper/klippy/serialhdl.py", line 263, in raw_send_wait_ack
    self._error("Serial connection closed")
  File "/opt/klipper/klippy/serialhdl.py", line 68, in _error
    raise error(self.warn_prefix + (msg % params))
serialhdl.error: mcu 'mcu': Serial connection closed

I have confirmed that it loads the included printer-simulavr.cfg file.

---

$ git diff docker-compose.extra.simulavr.yaml
diff --git a/docker-compose.extra.simulavr.yaml b/docker-compose.extra.simulavr.yaml
index 1194b9d..f43c3b3 100644
--- a/docker-compose.extra.simulavr.yaml
+++ b/docker-compose.extra.simulavr.yaml
@@ -7,7 +7,7 @@ services:
       context: docker/klipper
       target: build-simulavr
       args:
-        VERSION: master
+        VERSION: 2f05309d59743c1a20b271da3a8c481397c16424
     privileged: true
     volumes:
       - /dev:/dev

$ docker compose --profile mainsail --profile hostmcu -f docker-compose.yaml -f docker-compose.extra.simulavr.yaml exec klipper ls -l /opt/printer_data/run
total 0
srwxr-xr-x 1 klipper klipper  0 Jul  6 22:51 klipper.sock
lrwxrwxrwx 1 klipper klipper 10 Jul  6 22:49 klipper.tty -> /dev/pts/2
lrwxrwxrwx 1 root    root    10 Jul  6 22:45 klipper_host_mcu.tty -> /dev/pts/5
lrwxrwxrwx 1 klipper klipper 10 Jul  6 22:49 simulavr.tty -> /dev/pts/1

$ docker compose --profile mainsail --profile hostmcu -f docker-compose.yaml -f docker-compose.extra.simulavr.yaml exec klipper ls -l /dev/pts/1
crw--w---- 1 klipper tty 136, 1 Jul  6 22:52 /dev/pts/1

$ uname -a
Linux homelab 6.17.0-35-generic #35~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Tue May 26 19:30:42 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

$ docker --version
Docker version 29.5.2, build 79eb04c

---

Did a separate test with a real MCU (and host MCU) which connected fine, so things work in general, but I'm now a bit stuck setting up the simulator.

Am I missing something obvious here ?

[mkuf]

I was unable to reproduce this behaviour.
Please try to revert your changes in docker-compose.extra.simulavr.yaml to try with master instead of a specific commit.
Did you alter printer-simulavr.cfg due to the hostmcu profile being enabled?

[andersevenrud]

Please try to revert your changes in docker-compose.extra.simulavr.yaml to try with master instead of a specific commit.

Thanks, I'll try that.

Did you alter printer-simulavr.cfg due to the hostmcu profile being enabled?

I have not altered printer-simulavr.cfg. The plan was to use hostmcu once everything was up and running.

[andersevenrud]

I tried with master, but still same issue.

I'll try to poke around a bit more, and maybe test on another machine as well to see I can figure it out.