MSPM0C1104: Connection issue with MSPM0C1104 using XDS110

Hi Sourabh,

It seems the image you shared is not visible. Can you share it again? Also, what software tool are you using to program the device? Finally, can you prove the SWD lines to check if there is any signals coming from it?

Best Regards,

Diego Abad

This error we got while connecting the debugger.

Hi Sourabh,

The error you are seeing is typically attributed to an issue in hardware, such as with power supply.

There are several E2E threads related to this issue that may be helpful:

•  CCS/66AK2E05: PRSC module failed to write to a router register. 
•  AM335x error connecting to target: PRSC module failed to write to a router register 
•  c6748 CCS5 XDS510USB connection issue PRSC failed , -6305 
•  "Connect to PRSC failed" error with CCSv4.2 

The MSP team also performs schematic reviews on Fridays. If this is something you are interested in, please reach out to your local Technical Sales Representative (TSR) or Field Applications Engineer (FAE).

Best,

Owen

Dear Team,

I have tried all the above suggestions but still face PRSC -6305 error.

This circuit we are using in our boards



Please suggest to us, we are also ready for the conference call. Please share your availability. 

Hi Sourabh,

Based on your schematic, the only suggestion I have is to use a 47kOhm pull-up resistor on nRST, which is the recommended value.

From the , the error you observe occurs under theses causes:

With that in mind, are you writing to NONMAIN?

Can you probe and share a capture of the power supplied to the device when attempting to program the device?

Can you try using an external power supply for the MSPM0C1104, rather than from the motor driver?

Have you tried an A-B-A swap of the device on your board?

Best,

Owen

We have changed the resistor to 47kohm.

Also, if we are supplying AVdd from an external source, then the MCU is programmed. And no PRSC error is observed.

But if the external PS is removed and AVdd connects, the voltage drops 1.8-2.2V.

What is the cause of it?

Hi Sourabh,

The issue is likely that the motor driver is also drawing current when you are flashing the MSPM0C1104. I would suggest using an external power supply if possible, but if that is not possible, then I would suggest keeping the motor driver in a low power mode or sleep/shutdown mode while debugging the MSPM0C1104.

Best,

Owen

Hi,

We are using a 47 kΩ pull-up resistor on the NRST pin.

When the JTAG debugger is connected, after programming the PCB for the first time and attempting to run the fan, the MCU remains in a hold or reset condition.

In the next step, when the JTAG is disconnected and the power is reset, the PCB runs normally, and the fan operates as expected.

It appears that the external pull-up resistor on NRST, together with internal resistors inside the JTAG interface connected to ground, may be forming a potential divider.

This could be pulling the NRST pin low and keeping the MCU in reset while the debugger is connected.

Is there any specific calculation or guideline for selecting the value of the pull-up resistor on the NRST pin?

In particular, is 47 kΩ appropriate, or should a lower value be used to ensure a valid reset level when JTAG is connected?

Hi Sourabh,

The 47kOhm pull-up resistor on NRST is the recommended value per the device datasheet:

Did you probe the NRST pin and observe that it was being held low?

What are your steps to initially flashing the device? Are you directly flashing the code or are you starting a debug session? (Share screenshots if possible)

Best,

Owen