ISP-IAP API Debugging

Comparing flash images

Depending on the debugger used and the IDE debug settings, the memory that is visible when the debugger connects might be the boot ROM, the internal SRAM, or the flash. To help determine which memory is present in the current debug environment, check the value contained at flash address 0x0000 0004. This address contains the entry point to the code in the ARM Cortex-M0+ vector table, which is the bottom of the boot ROM, the internal SRAM, or the flash memory respectively.

Table 1. ISP-IAP API Memory mapping in debug mode
Memory mapping mode Memory start address visible at 0x0000 0004
Bootloader mode 0x1FFF 0000
User flash mode 0x0000 0000
User SRAM mode 0x1000 0000

Serial Wire Debug (SWD) flash programming interface

Debug tools can write parts of the flash image to RAM and then execute the IAP call "Copy RAM to flash" repeatedly with proper offset.