void setup() {
	SERIAL.begin(BAUDRATE);

	pinMode(LED_PMODE, OUTPUT);
	pulse(LED_PMODE, 2);
	pinMode(LED_ERR, OUTPUT);
	pulse(LED_ERR, 2);
	pinMode(LED_HB, OUTPUT);
	pulse(LED_HB, 2);

// 1YEN[201118]
	// clock output (D3)
	pinMode (3, OUTPUT);
	// TC2 setting
	// OC2B pwm output, fast pwm OCR2A mode 7, fcpu/1
	TCCR2A=0x23;
	TCCR2B=0x09;
	OCR2A=0x01;
	OCR2B=0x00;
	TCNT2=0x00;
}