I need to interface weighing scale with Arduino UNO to see the weighing scale data in serial monitor of arduino ide. That weighing scale has rs232 port for communication. Weighing scale sends weight data whenever we send the "R" to the weighing scale. I am new to arduino programming.BElow is my code.
RS232 can use different voltage levels. Some of it are incompatible with arduino ports. Do you know exact characteristics of your scale rs232 interface?
There's more to an RS232 device interface than the TxD and RxD signals. You need to read the user manual for the scales to see if it uses handshaking (either hardware or software).
Do you have a schematic of your RS232-TTL converter?
You may need to override the hardware handshaking in order to get your scales to send data. It's been a while since i played with DB-9 RS232, but you may need to put a wire link between pins 4&6 and another between pins 7&8 if this ins't already done on your RS232-TTL midule.