Documentation

// Blink sketch for Arduino Pro Mini, uploaded via FT232RL
// Steps in Arduino IDE:
//  1. Tools -> Board: Arduino Pro or Pro Mini
//  2. Tools -> Processor: ATmega328P (5V, 16 MHz) or (3.3V, 8 MHz)
//  3. Tools -> Port: select the FT232RL COM/tty port
//  4. Click Upload

const int LED = 13;

void setup() {
  pinMode(LED, OUTPUT);
  Serial.begin(9600);
  Serial.println("Pro Mini online via FT232RL");
}

void loop() {
  digitalWrite(LED, HIGH);
  delay(500);
  digitalWrite(LED, LOW);
  delay(500);
}

#!/usr/bin/env python3
# Read lines from any device connected to the FT232RL.
# Install dependency: pip install pyserial

import serial
import time

# Replace with your port:
#   Linux/macOS: '/dev/ttyUSB0' (Linux) or '/dev/tty.usbserial-XXXX' (macOS)
#   Windows:    'COM3', 'COM4', etc.
PORT = '/dev/ttyUSB0'
BAUD = 9600

with serial.Serial(PORT, BAUD, timeout=1) as ser:
    time.sleep(2)  # let the device reset on DTR toggle
    print(f"Listening on {PORT} at {BAUD} baud. Ctrl+C to stop.")
    try:
        while True:
            line = ser.readline().decode('utf-8', errors='replace').rstrip()
            if line:
                print(line)
    except KeyboardInterrupt:
        print("\nStopped.")

# Flash a firmware image to an ESP-01 / ESP8266 via the FT232RL.
# Requires: pip install esptool
# Hold GPIO0 to GND while powering on the ESP-01 to enter flash mode.

# 1. Verify the ESP8266 is responding
esptool.py --port /dev/ttyUSB0 --baud 115200 chip_id

# 2. Erase existing flash (optional but recommended)
esptool.py --port /dev/ttyUSB0 --baud 115200 erase_flash

# 3. Write new firmware (replace path with your .bin file)
esptool.py --port /dev/ttyUSB0 --baud 115200 write_flash 0x00000 firmware.bin

# After flashing: disconnect GPIO0 from GND and reset the ESP-01 to run.

# Find the FT232RL port (Linux: /dev/ttyUSB*; macOS: /dev/tty.usbserial-*)
ls /dev/ttyUSB* 2>/dev/null
ls /dev/tty.usbserial-* 2>/dev/null

# Open a serial console at 115200 baud (common for Raspberry Pi)
# Linux/macOS: screen
screen /dev/ttyUSB0 115200

# Exit screen with: Ctrl+A then K, then Y to confirm.

# Alternative: minicom (Linux)
sudo apt install minicom
minicom -D /dev/ttyUSB0 -b 115200