BOOSTXL-DRV8305EVM: SPI kommunikation reponse always zero

Uwe,

Have you tried this experiment using the LAUNCHXL-F28027F as the kit is originally designed? Do you see the same issue?

Regards,

-Adam

Hello Adam,

we do not have any other eval boards, except the LAUNCHXL2-570LC43. I think this should not be an issue because its just a simple SPI connection.

Regards,

Uwe

Uwe,

Are you using the BOOSTXL-DRV8305EVM? This board must be used with the LAUNCHXL-F28027F board. These two come as a kit.

The LAUNCHXL2-570LC43 is a different processor and hardware than the intended LAUNCHXL-F28027F which is probably causing your issues.

Please show us how you have the two boards connected.

Some questions about your transmission:

1. Is your SCLK low when nSCS transistions?
2. Please confirm which register are you trying to read?
3. Have you tried a few other registers?

Regards,

-Adam

Adam,

Yes, I am using the BOOSTXL-DRV8305EVM and I have the same issue reading all registers. We want to use the BOOSTXL-DRV8305EVM in combination with the TMS570LC43 LAUNCHPAD XL2. As you can see in my first post, SDO (green signal 4) is going low during transmission. By removing nSCS the signal SDO is staying high.
The BOOSTXL-DRV8305EVM is connected to MIBSPI3 using a breadboard.
SCLK is low when nSCS when transistions (80 ns).

Regards,
Uwe

Uwe,

I need to see how the two boards are connected to eachother. Please show me a clear picture or similar.

Regards,

-Adam

Adam,

here is a list showing the wirings. SDO is pulled up with a 1k resistor.

 

Regards,

Uwe

Uwe,

Have you checked if the MCU has an internal pull down for SDO?

Can you disconnect everything on SDO except the pull-up resistor and using a high impedance probe, check for output on SDO?

Regards,

-Adam

Adam,

I have attached the HALCoGen file to show you the LAUNCHXL2-570LC43 setting. I am pretty sure the MIBSPI setting is correct. I also tried another BOOSTXL board. It's the same issue.

Regards,

Uwe

Booster.zip

Uwe,

Did you try the experiment I mentioned?

Regards,

-Adam

Adam,

Yes I did. I've disconnected only the SDO from the MCU and checked the output signal. The result is like in my first post. DSO is driving low during transmission (the green line in the scope picture).

Regards,

Uwe

Uwe,

Are you able to write to the device? Do you have any proof that the writes are working or not?

Please send me your register writes that you are making before you read back unsuccessfully.

I will try this on my EVM and get back to you.

Regards,

-Adam

Adam,

I can't write any register. Reading back registers I am getting always the same result: DSO is staying low during transmission. See picture of my oscilloscope.

In this example I am writing and reading register seven.

1 = SCLK, 2 = SDI, 3 = SCS, 4 = SDO

Regars,

Uwe