KevinOConnor
commented
3 years ago Interesting.
I suspect there are two separate issues - lcd init sequence and micro-controller timing. The micro-controller timing is likely to be the larger issue.
Klipper expects the micro-controller timing to be steady and reliable. The host code measures the micro-controller clock rate (by comparing it to the host machines system time) and expects that it can make generally accurate predictions about the micro-controller clock. In addition, the micro-controller expects that it will get a schedule of events that it can reliably run without falling behind by a significant amount. A "Rescheduled timer in the past" error indicates the micro-controller detected it could not keep up with its schedule of events. That's certainly an odd error to get during the initialization process, as the micro-controller has a very limited schedule at that point.
Some random hints:
- Grab the very latest code. The change for #3356 may help here.
- Reduce your printer.cfg to the simplest possible and then add features on top until you run into an issue. An example minimal config looks something like:
[mcu] serial: /dev/ttyACM0
[printer] kinematics: none max_velocity: 300 max_accel: 1000
3. It's possible there is an error in the simavr timer emulation. If so, that may require work on simavr itself.
4. If you get a klipper shutdown, it's possible to post-process that log - see: https://www.klipper3d.org/Debugging.html#extracting-information-from-the-klippylog-file
As for the LCD display - the hd44780 bit-banging interface is pretty cryptic. Klipper uses a "hack" to make sure the display is in "4-bit mode". You'll find that init code in klippy/extras/display/hd44780.py:
```python
# Program 4bit / 2-line mode and then issue 0x02 "Home" command
init = [[0x33], [0x33], [0x33, 0x22, 0x28, 0x02]]
# Reset (set positive direction ; enable display and hide cursor)
init.append([0x06, 0x0c])I suspect that sequence is confusing the simulator and it gets out of sync with the 4bit mode. (Or, perhaps, the simulator gets stuck in 8-bit mode.) You could try simplifying the host init sequence to see if it helps (though I'd recommend tracking down the timing issues first).
-Kevin
vintagepc
Hello!
Let me prefix this by saying I don't have any expectation of support for this; I know full well it's way off the beaten path and into the jungle; That said; I'm hoping that someone with more experience interpreting the logs could save some time and point us at what might be going wrong. Now, on to the issue:
I had a request to support Klipper in MK404 (https://github.com/vintagepc/MK404/issues/263). It seemed fairly straightforward, given it can run stock Prusa firmware and Marlin - and Klipper also is capable of running in a simulated environment through simulavr. (MK404 is built on SimAVR instead).
Alas we are having some issues very early in the startup process and I was hoping someone might be able to shed some light on either the issue or the debugging mechanisms/outputs available (if any) beyond straight-up avr-gdb on the simulator, which would require an in-depth knowledge of its workings beforehand.
So far we've determined something appears to be going wrong very early on in the process - the display doesn't even initialize correctly and just shows garbage:
I monitored the simulated display and it almost looks like the 4 bit nibbles are swapped when compared to the display data sections in the Klipper log, suggesting a synchronization problem.
Display VRAM write log
``` ProcessWrite command 0write when still BUSY ProcessWrite command write when still BUSY OnCmdReadyactivating 4-bit mode hd44780_write_data 02 () to 48 hd44780_write_data 02 () to 47 hd44780_write_data 02 () to 46 hd44780_write_data 02 () to 45 hd44780_write_data 02 () to 44 hd44780_write_data 02 () to 43 hd44780_write_data 02 () to 42 hd44780_write_data 02 () to 41 hd44780_write_data 82 (�) to 40 hd44780_write_data 02 () to 27 hd44780_write_data 02 () to 26 hd44780_write_data 02 () to 25 hd44780_write_data 02 () to 24 hd44780_write_data 02 () to 23 hd44780_write_data 02 () to 22 hd44780_write_data 02 () to 21 hd44780_write_data 02 () to 20 hd44780_write_data 02 () to 1f hd44780_write_data 02 () to 1e hd44780_write_data 02 () to 1d hd44780_write_data 02 () to 1c hd44780_write_data 02 () to 1b hd44780_write_data 02 () to 1a hd44780_write_data 02 () to 19 hd44780_write_data 82 (�) to 18 hd44780_write_data 02 () to 17 hd44780_write_data 02 () to 16 hd44780_write_data 02 () to 15 hd44780_write_data 02 () to 14 hd44780_write_data 02 () to 13 hd44780_write_data 02 () to 12 hd44780_write_data 02 () to 11 hd44780_write_data 02 () to 10 hd44780_write_data 02 () to 0f hd44780_write_data 02 () to 0e hd44780_write_data 02 () to 0d hd44780_write_data 02 () to 0c hd44780_write_data 02 () to 0b hd44780_write_data 02 () to 0a hd44780_write_data 02 () to 09 hd44780_write_data 02 () to 08 hd44780_write_data 02 () to 07 hd44780_write_data 02 () to 06 hd44780_write_data 02 () to 05 hd44780_write_data 02 () to 04 hd44780_write_data 02 () to 03 hd44780_write_data 02 () to 02 hd44780_write_data 02 () to 01 hd44780_write_data 82 (�) to 00 hd44780_write_data 02 () to 67 hd44780_write_data 02 () to 66 hd44780_write_data 02 () to 65 hd44780_write_data 02 () to 64 hd44780_write_data 02 () to 63 hd44780_write_data 02 () to 62 hd44780_write_data 02 () to 61 hd44780_write_data 02 () to 60 hd44780_write_data 02 () to 5f hd44780_write_data 02 () to 5e hd44780_write_data 02 () to 5d hd44780_write_data 02 () to 5c hd44780_write_data 02 () to 5b hd44780_write_data 02 () to 5a hd44780_write_data 02 () to 59 hd44780_write_data 82 (�) to 58 hd44780_write_data 02 () to 57 hd44780_write_data 02 () to 56 hd44780_write_data 02 () to 55 hd44780_write_data 02 () to 54 hd44780_write_data 02 () to 53 hd44780_write_data 02 () to 52 hd44780_write_data 02 () to 51 hd44780_write_data 02 () to 50 hd44780_write_data 02 () to 4f hd44780_write_data 02 () to 4e hd44780_write_data 02 () to 4d hd44780_write_data 02 () to 4c hd44780_write_data 02 () to 4b hd44780_write_data 02 () to 4a hd44780_write_data 02 () to 49 hd44780_write_data 00 () to 48 hd44780_write_data 00 () to 47 hd44780_write_data 00 () to 46 hd44780_write_data 00 () to 45 hd44780_write_data 00 () to 44 hd44780_write_data 00 () to 43 hd44780_write_data 00 () to 42 hd44780_write_data 00 () to 41 hd44780_write_data 00 () to 40 hd44780_write_data 00 () to 27 hd44780_write_data 00 () to 26 hd44780_write_data 00 () to 25 hd44780_write_data 00 () to 24 hd44780_write_data 00 () to 23 hd44780_write_data 00 () to 22 hd44780_write_data 00 () to 21 hd44780_write_data 00 () to 20 hd44780_write_data 00 () to 1f hd44780_write_data 00 () to 1e hd44780_write_data 00 () to 1d hd44780_write_data 00 () to 1c hd44780_write_data 00 () to 1b hd44780_write_data 00 () to 1a hd44780_write_data 00 () to 19 hd44780_write_data 00 () to 18 hd44780_write_data 00 () to 17 hd44780_write_data 00 () to 16 hd44780_write_data 00 () to 15 hd44780_write_data 00 () to 14 hd44780_write_data 00 () to 13 hd44780_write_data 00 () to 12 hd44780_write_data 00 () to 11 hd44780_write_data 00 () to 10 hd44780_write_data 00 () to 11 hd44780_write_data 00 () to 12 hd44780_write_data 00 () to 13 hd44780_write_data 00 () to 14 hd44780_write_data 00 () to 15 hd44780_write_data 00 () to 16 hd44780_write_data 00 () to 17 hd44780_write_data 00 () to 18 hd44780_write_data 00 () to 19 hd44780_write_data 00 () to 1a hd44780_write_data 00 () to 1b hd44780_write_data 00 () to 1c hd44780_write_data 00 () to 1d hd44780_write_data 00 () to 1e hd44780_write_data 00 () to 1f hd44780_write_data 00 () to 20 hd44780_write_data 00 () to 21 hd44780_write_data 00 () to 22 hd44780_write_data 00 () to 23 hd44780_write_data 00 () to 24 hd44780_write_data 00 () to 25 hd44780_write_data 00 () to 26 hd44780_write_data 00 () to 27 hd44780_write_data 00 () to 40 hd44780_write_data 00 () to 41 hd44780_write_data 00 () to 42 hd44780_write_data 00 () to 43 hd44780_write_data 00 () to 44 hd44780_write_data 00 () to 45 hd44780_write_data 00 () to 46 hd44780_write_data 00 () to 47 hd44780_write_data 00 () to 48 hd44780_write_data 02 () to 49 hd44780_write_data 02 () to 4a hd44780_write_data 03 () to 4b hd44780_write_data 00 () to 4c hd44780_write_data 00 () to 14 hd44780_write_data 40 (@) to 15 hd44780_write_data a0 (�) to 16 hd44780_write_data a0 (�) to 17 hd44780_write_data a0 (�) to 18 hd44780_write_data a1 (�) to 19 hd44780_write_data 11 () to 1a hd44780_write_data 10 () to 1b hd44780_write_data 81 (�) to 65 hd44780_write_data c1 (�) to 66 hd44780_write_data 01 () to 67 hd44780_write_data 81 (�) to 00 hd44780_write_data 00 () to 47 hd44780_write_data e0 (�) to 48 hd44780_write_data e0 (�) to 49 hd44780_write_data e1 (�) to 4a hd44780_write_data f1 (�) to 4b hd44780_write_data f1 (�) to 4c hd44780_write_data f0 (�) to 4d hd44780_write_data 40 (@) to 4e ```At some point after that Klipper throws a "timer scheduled in the past" error, but I suspect that once things have gone wrong any downstream errors are not necessarily related to the problem, just side effects. The display itself probably isn't even the initial issue either, but I'm not seeing any obvious faults further upstream in the Klipper log.
Thanks in advance for any insight you can provide!
log.txt