Hi, SaiDe,
Generally, user can use JTAG port to program internnal flash based on CodeWarrior tools or the other tools. If you want to use serial port to program flash, you have to use bootloader mode, in other words, Firstly, you have to write the bootloader code to flash of MC56F84789 with CodeWarrior for mcu tools via JTAG port, after reset, the bootloader is run firstly, poll the serial port, if there is data received from serial port at the predefined time, the bootloader will accept the application code and write or update it to flash. If it can not receive code within the predefined time, it will jump to application code directly.
BTW, you can download an4759.pdf for the bootloader utilization.
This is the bootloader code.
Hope it can help you
BR
Xiangjun rong
