FTDI USB-Serial cable header is a 6-pin 2.54mm connector carrying USB-to-UART signals at 3.3V or 5V for programming Arduino Pro Mini, ESP-01, and other boards without onboard USB.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | GND | Ground black wire | GND |
| 2 | CTS | Clear to send brown wire | BUS |
| 3 | VCC | Power supply red wire | PWR |
| 4 | TXD | Transmit data orange wire | BUS |
| 5 | RXD | Receive data yellow wire | BUS |
| 6 | DTR | Data terminal ready green wire | BUS |