✨ BigTreeTech SKRat V1.0 (STM32G0B1VE)

[thisiskeithb]

Description

Add BigTreeTech SKRat V1.0 support. I've reached out to @bigtreetech since everything appears to work correctly except for UART-based TMC drivers as they show ALL LOW / zeroed registers no matter what.

Error: All LOW

>>> M122
SENDING:M122
		X	Y	Z	Z2	E
Address		0	0	0	0	0
Enabled		false	false	false	false	false
Set current	800	800	800	800	800
RMS current	1436	1436	1436	1436	1436
MAX current	2025	2025	2025	2025	2025
Run current	25/31	25/31	25/31	25/31	25/31
Hold current	12/31	12/31	12/31	12/31	12/31
CS actual	0/31	0/31	0/31	0/31	0/31
PWM scale
vsense		0=.325	0=.325	0=.325	0=.325	0=.325
stealthChop	false	false	false	false	false
msteps		256	256	256	256	256
interp		false	false	false	false	false
tstep		0	0	0	0	0
PWM thresh.
[mm/s]
OT prewarn	false	false	false	false	false
triggered
 OTP		false	false	false	false	false
pwm scale sum	0	0	0	0	0
pwm scale auto	0	0	0	0	0
pwm offset auto	0	0	0	0	0
pwm grad auto	0	0	0	0	0
off time	0	0	0	0	0
blank time	16	16	16	16	16
hysteresis
 -end		-3	-3	-3	-3	-3
 -start		1	1	1	1	1
Stallguard thrs	0	0	0	0	0
uStep count	0	0	0	0	0
DRVSTATUS	X	Y	Z	Z2	E
sg_result	0	0	0	0	0
stst		*	*	*	*	*
olb
ola
s2gb
s2ga
otpw
ot
157C
150C
143C
120C
s2vsa
s2vsb
Driver registers:
		X	0x00:00:00:00	 Bad response!
		Y	0x00:00:00:00	 Bad response!
		Z	0x00:00:00:00	 Bad response!
		Z2	0x00:00:00:00	 Bad response!
		E	0x00:00:00:00	 Bad response!
Testing X connection... Error: All LOW
Testing Y connection... Error: All LOW
Testing Z connection... Error: All LOW
Testing Z2 connection... Error: All LOW
Testing E connection... Error: All LOW

I'm well aware of the usual suspects when it comes to TMC driver issues and I've already tried them all on two different SKRat boards:

• Powered from external 24V source
• Verified UART jumpers are set correctly under each driver
• Tested with TMC2225s, TMC2208s, TMC2226s, and TMC2209s. Each type show ALL LOW errors for every driver. The same drivers work fine in other boards.
• Verified pins file matches board's pins drawing & schematics as well as Klipper config
• Verified the correct driver types were enabled in the config

Other things to note:

• SPI TMC drivers work fine
• UART drivers work fine under Klipper

I've also re-added theSTM32G0B1VE_btt_xfer environment since it is compatible with this board and I've verified that it works.