ICE error: 6603H occurs in the following cases. (1) Poor connection between the on-chip emulator and the microcontroller (2) Microcontroller failure Check the following. ・ Is there a problem with the connection / contact of the interface cable? ・ Are any components such as resistors or capacitors that cannot be connected when using an on-chip emulator connected to RESET_N or TEST0? If there are no problems with these, the microcontroller you are using may be defective. Please replace the microcontroller and try again.