is there a way how to force mc68hc908 mcu to enter in the bootloader to change the firmware to new one. really appreciate your kind help
Hello and welcome to the fora,
That would depend on the bootloader you have installed.
If you mean to enter Monitor mode then it is all spelled out in the datasheet.
Section 18.3 Development Support/Monitor Module
Have a look in there and come back here if still unsure.
thanks for your reply. I think that you are refering for figure 18-10 and figure 18-11. But the MCU is in circuit and it has a bootloader and a firmware. What I need it to stop the MCU to enter in bootloader to upload the firmware. I think that the circuit is not good for this.
Yes, Peg was referring to that circuit and the "Monitor-Mode" bootloader that comes pre-programmed into the GP32.
If your PCB does not have the circuit necessary, as shown in Figures 18-9, 18-10 and 18-11, then you can not use Monitor-Mode. Monitor-Mode is the only bootloader that comes with the GP32.
If you are saying that your GP32 has an additional bootloader that was installed with your original firmware, then you need to find the person who wrote it to find out how it is supposed to work.
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