DTE Interface
Rev. Bb
December 2020
The Mini RS232 Seriel TTL Converter from China is a compact UART to RS232 Converter Module for out connection the Arduino to the LOGO! PG Cable.
I have create my own version, because I was not sure if the standard RS232 DB9 connectors are supports RTS (which is bridged to power the electronics in the PC cable). The product is not compatible to the 5-wire RS232 standard.
Figure RS232 Converter connected to the Arduino
- Convert TTL (Transistor-Transistor Logic) level signals to RS-232 interface
- D-SUB 9pin (RS232) MALE connector
- Supports 3V to 5.5V power supply (we must use 5V for our project)
- IC: MAX3232
- Pitch: 2.54mm
- RTS pin: connected to VCC
| Grove Pin | Name | Signal | Color |
|---|---|---|---|
| 4 | GND | Ground | black |
| 3 | VCC | Voltage 5V | red |
| 2 | ↑ TX | Transmit Data | white |
| 1 | ↓ RX | Receive Data | yellow |
Note: 1) DB9 Pin 6 have to be bridged to VCC to power the electronics in the PC cable. The system connected with the LOGO! cable must be able to supply at least 5 mA current through this Pin of its RS232 interface.
Figure PIN Layout of the Mini RS232 Seriel TTL Converter Board
Figure PIN Layout incl. the Grove connector