AM32/BLHeli ESC 1-Wire Linker for Arduino Uno & Nano

Wed, 01 Jul 2026 07:07:04 +0000

If you want to flash or configure your AM32/BLHeli ESC using just an Arduino, here's a quick sketch that turns your Uno or Nano into a 1-Wire passthrough interface.

Wiring:

For Arduino Nano → connect the ESC signal wire to pin D3

For Arduino Uno → connect the ESC signal wire to pin D11

For Arduino Mega → connect the ESC signal wire to pin D51

Ground always connects to GND

How to use:

Open the code below in Arduino IDE.

Select your board (Uno or Nano) under Tools > Board.

Upload the sketch — the correct pin is selected automatically based on your board choice.

Wire your ESC signal wire to the pin mentioned above, and ground to ground.

Connect to BLHeliSuite or AM32 configurator and flash your ESC.

Code:

#include

//1-Wire Pin:

//Arduino Nano only -> PD3="D3

//MEGA boards -> PB2="D51=MOSI"

//all other -> PB3="D11=MOSI

#define OW_PINB3

#if defined OW_PINB3

#define OW_DDR DDRB

#define OW_PORT PORTB

#define OW_PIN PINB

#define OW PINB3

#elif defined OW_PIND3

#define OW_DDR DDRD

#define OW_PORT PORTD

#define OW_PIN PIND

#define OW PIND3

#elif defined OW_PINB2

#define OW_DDR DDRB

#define OW_PORT PORTB

#define OW_PIN PINB

#define OW PINB2

#endif

#if (defined (_AVR_ATmega2560) || defined (AVR_ATmega1280_))

#define IN_DDR DDRE

#define IN_PORT PORTE

#define IN_PIN PINE

#define IN_RX PINE0

#define IN_TX PINE1

#else

#define IN_DDR DDRD

#define IN_PORT PORTD

#define IN_PIN PIND

#define IN_RX PIND0

#define IN_TX PIND1

#endif

#define SetOWout (OW_DDR|= (1<< OW))

#define SetOWin (OW_DDR &= ~(1<< OW))

#define SetOWlow (OW_PORT &= ~(1<< OW))

#define SetOWhigh (OW_PORT |= (1<< OW))

#define IsOWhigh (OW_PIN & (1<< OW))

#define IsOWlow (!(OW_PIN & (1<< OW)))

#define SetTXlow (IN_PORT &= ~(1<< IN_TX))

#define SetTXhigh (IN_PORT |= (1<< IN_TX))

#define IsRXhigh (IN_PIN & (1<< IN_RX))

#define IsRXlow (!(IN_PIN & (1<< IN_RX)))

int main(void)

{

//Very important disable hardware UART

UCSR0B =0;

IN_DDR |= (1<

IN_DDR &= ~(0<< IN_RX);

IN_PORT|= (1<

//SetOWin;//Set OW as input / default

SetOWhigh; //pull up on

while(IsRXhigh); //wait for RX go Low = 1 Incoming data

while(1)

{

//RX low = 1 -> set oneWire to output

SetOWout;

SetOWlow; //Set oneWire low =1

SetTXlow; //Echo low to TX

//Wait RX go high = 0 again

while(IsRXlow);

// input // RX is high (or high again) = 0 end of bit or idle - so listen to data from TRX

SetOWhigh; //Set OneWire High = 0 for sharper edge //can be skipped?

//and Echo low to TX

SetOWin;

SetOWhigh; //Set OneWire pull up

while (IsRXhigh) //while RX high (no incoming bytes)

{

if (IsOWhigh) SetTXhigh; //Set TX High = 0

else SetTXlow; //Set TX Low = 1

}

Get Started Now

TECHNOBOTIX - Blog #AM32

AM32/BLHeli ESC 1-Wire Linker for Arduino Uno & Nano

If you want to flash or configure your AM32/BLHeli ESC using just an Arduino, here's a quick sketch that turns your Uno or Nano into a 1-Wire passthrough interface.