Flash Programmer for NRF5340

[AlanXFong]

Dears, 

We are MCU Programmer Supplier, now we are developing the off-Line Programmer for NRF5340, and encounter some problem as below:

1. Does the Nrf5340 Flash Memory could be read directly read by SWD just like NRF51xx/52xx chips? we found that when we directly read Main Flash, the firse 4Kb data will be random, and the rest is OK(Blank chip to read FF), Why?

2. According to document, Network Core seems that use AP-Bnak 1 to access, if all register and memory flash must use AP-Bank 1 to access?

3. When use JLINK to burn some random testing data to chip, after power off (if not Power off), we can use JLINK to connect/disconnect and do verify), JLINK could not make correct connection. and when we to debug bys SWD, found that when SWD to write DHCSR it responses falut error.  But we can use CTRL-AP APID=2 to do EraseAll and back to factory default mode. Why?

Looking for you kindly support!

Best regards,

Alan

[dejans]

Hi Alan,

1. Does the Nrf5340 Flash Memory could be read directly read by SWD just like NRF51xx/52xx chips? we found that when we directly read Main Flash, the firse 4Kb data will be random, and the rest is OK(Blank chip to read FF), Why?

Take a look at this discussion. It explains why 4 KB binary stays in the recovered flash memory.

2. According to document, Network Core seems that use AP-Bnak 1 to access, if all register and memory flash must use AP-Bank 1 to access?

Could you specify which document are you referring to?

3. When use JLINK to burn some random testing data to chip, after power off (if not Power off), we can use JLINK to connect/disconnect and do verify), JLINK could not make correct connection. and when we to debug bys SWD, found that when SWD to write DHCSR it responses falut error.  But we can use CTRL-AP APID=2 to do EraseAll and back to factory default mode. Why?

Could you provide more details about the exact state (powering on/off) and the action you are taking in that step? Are you using nRF5340DK or a custom board? What are you referring to as DHCSR? Is there any reason why you would want to write to the DHCSR? What are you trying to write to it?  What is the error that you mentioned (when writing)? How do you use CTRL-AP APID=2 to perform EraseAll?

Best regards,
Dejan