DAP_ScanAP() function scans all the access ports for the first available access port with CPU register access. If the function returns true then the function was able to initialize an access port and get access to the ARM registers. Or else programming fails.
When the CPUID register is read the first 8 bits of the register [31:24] have to be equal to 0x41 indicating that it is an ARM device. You can find more information about the CPUID register at this link - ARM CPUID Register.
Is the status of the Read action true?
Can you confirm that the address of the CPUID register is provided correctly?
Can you please share your programming script?
Thanks and Regards,
Rakshith M B