Testing
Hardware
| Serial Port | Signal | Teensy 1.0 | Teensy 2.0 | Teensy++ 1.0 & 2.0 | Teensy LC | Teensy 3.0, 3.1, 3.2 | Teensy 3.5 & 3.6 | Teensy 4.0 | Teensy 4.1 |
|---|---|---|---|---|---|---|---|---|---|
| Serial1 | Receive | 2 | 7 | 2 | 0, 3, 21, 25 | 0, 21 | 0, 21, 27 | 0,(xbar) | 0,52,(xbar) |
| Transmit | 3 | 8 | 3 | 1, 4, 5, 24 | 1, 5 | 1, 5, 26 | 1 | 1,53 | |
| Transmit Enable | Any | Any | Any | Any | Any | Any | Any | Any | |
| RTS | – | – | – | Any | Any | Any | Any | Any | |
| CTS | – | – | – | – | 18, 20 | 18, 20 | (xbar*) | (xbar*) | |
| Serial2 | Receive | – | – | – | 9 | 9, 26 | 9 | 7,(xbar) | 7,(xbar) |
| Transmit | – | – | – | 10 | 10, 31 | 10 | 8 | 8 | |
| Transmit Enable | – | – | – | Any | Any | Any | Any | Any | |
| RTS | – | – | – | Any | Any | Any | Any | Any | |
| CTS | – | – | – | – | 23 | 23 | (xbar*) | (xbar*) | |
| Serial3 | Receive | – | – | – | 7, 6 | 7 | 7 | 15,(xbar) | 15,(xbar) |
| Transmit | – | – | – | 8, 20 | 8 | 8 | 14 | 14 | |
| Transmit Enable | – | – | – | Any | Any | Any | Any | Any | |
| RTS | – | – | – | Any | Any | Any | Any | Any | |
| CTS | – | – | – | – | 14 | 14 | 19,(xbar*) | 19,(xbar*) | |
| Serial4 | Receive | – | – | – | – | – | 31 | 16,(xbar) | 16,(xbar) |
| Transmit | – | – | – | – | – | 32 | 17 | 17 | |
| Transmit Enable | – | – | – | – | – | Any | Any | Any | |
| RTS | – | – | – | – | – | Any | Any | Any | |
| CTS | – | – | – | – | – | – | (xbar*) | (xbar*) | |
| Serial5 | Receive | – | – | – | – | – | 34 | 21,38,(xbar) | 21,46,(xbar) |
| Transmit | – | – | – | – | – | 33 | 20,39 | 20,47 | |
| Transmit Enable | – | – | – | – | – | Any | Any | Any | |
| RTS | – | – | – | – | – | Any | Any | Any | |
| CTS | – | – | – | – | – | 24 | 35,(xbar*) | 43,(xbar*) | |
| Serial6 | Receive | – | – | – | – | – | 47 | 25,(xbar) | 25,(xbar) |
| Transmit | – | – | – | – | – | 48 | 24 | 24 | |
| Transmit Enable | – | – | – | – | – | Any | Any | Any | |
| RTS | – | – | – | – | – | Any | Any | Any | |
| CTS | – | – | – | – | – | 56 | (xbar*) | (xbar*) | |
| Serial7 | Receive | – | – | – | – | – | – | 28,(xbar) | 28,(xbar) |
| Transmit | – | – | – | – | – | – | 29 | 29 | |
| Transmit Enable | – | – | – | – | – | – | Any | Any | |
| RTS | – | – | – | – | – | – | Any | Any | |
| CTS | – | – | – | – | – | – | (xbar*) | (xbar*) | |
| Serial8 | Receive | – | – | – | – | – | – | – | 34,48,(xbar) |
| Transmit | – | – | – | – | – | – | – | 35 | |
| Transmit Enable | – | – | – | – | – | – | – | Any | |
| RTS | – | – | – | – | – | – | – | Any | |
| CTS | – | – | – | – | – | – | – | 50,(xbar*) |