Motor driver won't talk to me :(

[RippoZero]

Got a pcb with a teensy 3.2 trying to talk to a motor driver(DRV8434s). I know information is transferred to the chip because I'm able to run a stepper motor, the signal from the micro also looks crisp. The problem is the DRV8434s SDO line, naturally it's connected to the standard MISO input for the micro. The signal is strange looking, it does not quite reach 3.3v and has a very slow rise time. It rests at about 0,  opposite to the MOSI signal, resting at 3.3v. I found this puzzling.

Among the things I've tried is lowering the frequency of the SPI bus, verifying values of supporting components, changing the IC, touching up solder joints and adding a pull-up resistor. Discovered I had connected the VSDO pin to the 3.3v rail though a resistor witch I swapped out for a wire.

Don't hesitate to ask if you want more information

[Psi]

What voltage is on these pins of the DRV8434

DVDD
VCP
VREF
NFAULT

[RippoZero]

DVDD - 5v
VCP - 17v
VREF - 3.3v
NFAULT - 340 mv

It's pulling nFault low 

[Psi]

First rule of troubleshooting, check voltages

What voltage is VM?
Your VCP voltage of 17V suggests VM must be around 10V but is that correct?

[RippoZero]

The datasheet specifies that nFault should be pulled up to DVDD if it's 5v logic, otherwise hocked up to external logic level. Since the logic level I'm using is 3.3v I made a goof here. Changed the pull-up resistor so it now bridges to 3.3v. The IC is now talking to the micro controller. Thank you very much Psi