Unable to read tmc uart 'selector_stepper' register IFCNT

General Discussion
1

klippy.log (97.1 KB)
Voron 2.4, RPI4
Octopus 1.1 24V USB serial
Mellow Fly ERCF board USB serial

Mellow Fly ERCF throws an “Unable to read tmc uart ‘selector_stepper’ register IFCNT” error

Describe your issue:

After about 100 hours of usage on my initial Mellow FLY ERCF board, I saw my klipper shutdown. My Fly ERCF at that point seemed to have dropped one of the heatsinks from the stepper drivers, potentially causing damage.

I have thoroughly looked at board/driver SMDs and found no issue. I have also tried jumping uart pin to another spare pin on the board to no avail.

Now here’s the funky part: I have just replaced both the board and the drivers for a brand new counterpart, flashed it for Serial connection, and the error still persists!

Here’s the tmc dump:

Unable to read tmc uart 'selector_stepper' register GCONF
========== Queried registers ==========
SGTHRS: 00000000
TPOWERDOWN: 00000014 tpowerdown=20
TPWMTHRS: 000fffff tpwmthrs=1048575
IHOLD_IRUN: 00080c04 ihold=4 irun=12 iholddelay=8
SLAVECONF: 00000200 senddelay=2
========== Write-only registers ==========
DUMP_TMC STEPPER=selector_stepper

Any ideas/help is appreciated.

2

To rule out a double fault: is it working fine with the other installed TMC drivers and what happens with a known good driver on the “failing” port configured as [selector_stepper]?

3

The solution was to look right under the nose and figure out that I somehow left a uart_address: 1 in the selector tmc configuration.