> 5.3 | Characteristics of the RS-232 interface

> Table 28: | Characteristics of the RS-232 interface

> Function | Signal name | IO | Signal from and level | Comment
> RS232 | TXD RTS DTR | I I I | R Imin = 3kOhm VILmax = 0.6V VIHmin = 2.4V VImax = ±25V | If lines are unused keep pin open. It could be possible to start the module with DTR.
> | RXD CTS DSR DCD RING | O O O O O | V Omin = ±5V at 3kOhm load Leakage Current max = ±25µA at Module power down.