Question:
When Fast bootloadable application validation is enabled in Bootloader Component for PSoC® 3, PSoC 4, or PSoC 5LP devices, comparison of PSoC device flash checksum and input hex file checksum fails (Checksum, F6). PSoC Programmer reports an error message: ‘Mismatches with HEX file’. What is the reason for this?
Figure 1: Mismatches with Hex file
When the Fast bootloadable application validation parameter is enabled in the Bootloader Component, the bootloader validates application only once and updates the Bootloadable Application Verification Status byte in the metadata region. On subsequent resets, the bootloader checks the Bootloadable Application Verification Status byte for validity of the bootloadable application. Therefore, the checksum of the device flash changes from the original checksum stored in the hex file, which leads to the Checksum (F6) operation from PSoC Programmer resulting in the “Mismatches with HEX file” error.
Figure 2. Fast Bootloadable Application Validation Setting
References
AN73854 - PSoC® 3, PSoC 4, and PSoC 5LP Introduction to Bootloaders