| RS-232 | EIA-530 | RS-449 | V.35 | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Signal Name | Source | Mnemonic | Pin | Mnemonic | Pin | Mnemonic | Pin | Mnemonic | Pin |
| Shield | -- | -- | 1 | -- | 1 | -- | 1 | -- | A |
| Transmitted Data | DTE | BA | 2 | BA (A) | 2 | SD (A) | 4 | 103 | P |
| BA (B) | 14 | SD (B) | 22 | 103 | S | ||||
| Received Data | DCE | BB | 3 | BB (A) | 3 | RD (A) | 6 | 104 | R |
| BB (B) | 16 | RD (B) | 24 | 104 | T | ||||
| Request To Send | DTE | CA | 4 | CA (A) | 4 | RS (A) | 7 | 105 | C |
| CA (B) | 19 | RS (B) | 25 | ||||||
| Clear To Send | DCE | CB | 5 | CB (A) | 5 | CS (A) | 9 | 106 | D |
| CB (B) | 13 | CS (B) | 27 | ||||||
| DCE Ready (DSR) | DCE | CC | 6 | CC (A) | 6 | DM (A) | 11 | 107 | E |
| CC (B) | 22 | DM (B) | 29 | ||||||
| DTE Ready (DTR) | DTE | CD | 20 | CD (A) | 20 | TR (A) | 12 | 108 | H * |
| CD (B) | 23 | TR (B) | 30 | ||||||
| Signal Ground | -- | AB | 7 | AB | 7 | SG | 19 | 102 | B |
| Recv. Line Sig. Det. (DCD) | DCE | CF | 8 | CF (A) | 8 | RR (A) | 13 | 109 | F |
| CF (B) | 10 | RR (B) | 31 | ||||||
| Trans. Sig. Elemt. Timing | DCE | DB | 15 | DB (A) | 15 | ST (A) | 5 | 114 | Y |
| DB (B) | 12 | ST (B) | 23 | 114 | AA | ||||
| Recv. Sig. Elemt. Timing | DCE | DD | 17 | DD (A) | 17 | RT (A) | 8 | 115 | V |
| DD (B) | 9 | RT (B) | 26 | 115 | X | ||||
| Local Loopback | DTE | LL | 18 | LL | 18 | LL | 10 | 141 | L * |
| Remote Loopback | DTE | RL | 21 | RL | 21 | RL | 14 | 140 | N * |
| Ring Indicator | DCE | CE | 22 | -- | -- | -- | -- | 125 | J * |
| Trans. Sig. Elemt. Timing | DTE | DA | 24 | DA (A) | 24 | TT (A) | 17 | 113 | U * |
| DA (B) | 11 | TT (B) | 35 | 113 | W * | ||||
| Test Mode | DCE | TM | 25 | TM | 25 | TM | 18 | 142 | NN* |