On-vehicle electronic controller

An on-vehicle electronic controller comprising:

• a microprocessor including a nonvolatile memory, in which at least one of a control program for a controlled vehicle and a control constant are written from an external tool, and a RAM memory for computing;
• an integrated circuit including a direct input interface circuit and a direct output interface circuit that are connected to a data bus of the microprocessor, one or more indirect input interface circuits, one or more variable filter circuits having constant setting register, and a communication control circuit;
• and
• an interactive serial communication circuit for transmitting a plurality of external input signals to the RAM memory, the signals being inputted via the one or more indirect input interface circuits, and for transmitting a filter constant stored in the nonvolatile memory to the constant setting register of the variable filter circuit.