DA14541 USB Development Kit as Programmer: SWDIO & Reset

Question

Good morning, 
 I am transitioning from the DA14531 USB Dev Kit to a custom prototype board. I was able to correctly configure the Dev Kit for programming per the serial wire debug guide. The custom prototype is now recognized by the Keil IDE and can enter debug mode. 
 
 However, when attempting to run the code there is an issue with CPU being halted which I believe is related to the reset line. Log below: 
 * JLink Info: Memory map 'after startup completion point' is active * JLink Info: CPU could not be halted ***JLink Error: Cannot read register 15 (R15) while CPU is running ***JLink Error: Cannot read register 16 (XPSR) while CPU is running ***JLink Error: Cannot read register 0 (R0) while CPU is running ***JLink Error: Cannot read register 1 (R1) while CPU is running ***JLink Error: Cannot read register 2 (R2) while CPU is running ***JLink Error: Cannot read register 3 (R3) while CPU is running ***JLink Error: Cannot read register 4 (R4) while CPU is running ***JLink Error: Cannot read register 5 (R5) while CPU is running ***JLink Error: Cannot read register 6 (R6) while CPU is running ***JLink Error: Cannot read register 7 (R7) while CPU is running ***JLink Error: Cannot read register 8 (R8) while CPU is running ***JLink Error: Cannot read register 9 (R9) while CPU is running ***JLink Error: Cannot read register 10 (R10) while CPU is running ***JLink Error: Cannot read register 11 (R11) while CPU is running ***JLink Error: Cannot read register 12 (R12) while CPU is running ***JLink Error: Cannot read register 13 (R13) while CPU is running ***JLink Error: Cannot read register 14 (R14) while CPU is running ***JLink Error: Cannot read register 15 (R15) while CPU is running ***JLink Error: Cannot read register 16 (XPSR) while CPU is running ***JLink Error: Cannot read register 17 (MSP) while CPU is running ***JLink Error: Cannot read register 18 (PSP) while CPU is running ***JLink Error: Cannot read register 20 (CFBP) while CPU is running 
 
 My questions are: 
 1. Is this error likely due to the reset line being disconnected? 
 2. How do I connect BOTH the SWDIO pin AND Reset from my custom PCB to the USB dev kit given that the SWDIO connection (per serial wire debug guide) uses the connection labeled as RES on the actual silk layer of the USB dev kit? 
 
 *I currently have P0_0 multiplexed with UART_TX and Reset by using a resistor to for the connection. Only UART_TX was connected on the custom PCB.

OV_Renesas · Answer

Hi There, Thank you for posting your question online. I suppose you have followed the procedure shown here: 20. Serial Wire Debug Probe &mdash; DA145XX Tutorial SDK Getting started 
 Nate said: 1. Is this error likely due to the reset line being disconnected? 
 On your Keil project please go on Options for Target and on Utilities make sure you have selected the highlighted option: 
 Nate said: 2. How do I connect BOTH the SWDIO pin AND Reset from my custom PCB to the USB dev kit given that the SWDIO connection (per serial wire debug guide) uses the connection labeled as RES on the actual silk layer of the USB dev kit? 
 There is no need to connect Reset pin. You only need SWDIO, SWCLK, VBAT and GND. Best Regards, OV_Renesas

OV_Renesas · Answer

Hi Nate, Thank you for the reply. Did you see the device advertising/scanning as expected when the FW was loaded into SRAM? You could also try to use SEGGER Ozone to debug your project in case Keil IDE is not responding. Please refer here: 5. Debugging using Ozone &mdash; DA145XX Tutorial SDK Getting started Best Regards, OV_Renesas

OV_Renesas · Answer

Hi Nate, Thank you for the reply. Could you please try to use SmartSnippets Toolbox and download your FW directly into RAM? We would like to verify that the custom board is working properly and then we can see why the debugger cannot be attached. You can get SmartSnippets Toolbox from here: SmartBond Development Tools | Renesas You can either use SWD or UART programming to download the FW into the SRAm. Best Regards, OV_Renesas

OV_Renesas · Answer

Hi Nate, Thank you for the reply. 
 Nate said: My understanding was that I could use the DA14531's internal 32kB OTP memory for firmware storage. 
 Yes, if your firmware is small you can store it in the OTP. Please refer here: 10. Boot from OTP and here: 17. OTP Programming &mdash; DA145XX Tutorial SDK Getting started You will find the necessary changes in order to store your FW on the OTP and boot from there. While you are in development stage, please do not flash the OTP (One Time Programmable) since you are not going to be able to change this. You should only download your FW into the SRAM in order to test it. 
 Nate said: For the buck configuration, my schematic probably isn't following conventions but does have a connection from VBAT_High to the power source shown on the battery protection circuit: 
 
 Could you please run some tests on your custom board. Check the Voltage level on VBAT_High and VBAT_low when you have downloaded your FW into the SRAM. If possible probe an oscilloscope on the XTAL Pins and check the behavior during boot time. Please also refer here as a reference: DA1453x Hardware Design Examples &mdash; DA14531 Hardware Design Examples Best regards, OV_Renesas

DA14541 USB Development Kit as Programmer: SWDIO & Reset

Top Replies