I hope you're all doing well. Today, I would like to seek your guidance on a specific topic: how to establish communication between a dot matrix printer and an Arduino Uno using serial communication (RS232).
I am interested in learning the necessary steps and components involved in connecting the Arduino Uno to a dot matrix printer via the RS232 interface. Specifically, I would like to understand how to send data from the Arduino to the printer and receive any response or acknowledgments.
Your insights, guidance, and any relevant resources you can share would be greatly appreciated. I am eager to delve into this project and expand my knowledge in the field of serial communication.
Thank you all for your assistance, and I look forward to your valuable input.
The Uno Serial interface uses TTL level signals which are not compatible with the RS232 of the printer so the first thing that you will need is a converter between the two
After that it is just a case of using the correct baud rate for the serial interface and the two devices can interchange data
so unless he already have a manual for his printer, then the next step after the hardware setup would be to 'sniff' the serial comms between PC and printer and from there try to establish the series of commands/strings to be sent to allow a successful print out.
for that, a 'serial bridge' might be useful to understand the flow of command to/from printer (probably a MEGA would be most practical here...)
So code like this one should do as Serial sniffer/bridge I should think:
//Uses an Arduino MEGA
uint8_t c;
void setup() {
Serial.begin(115200); //MEGA USB connection to print out sniffed serial bus data
//make it as fast as you can to reduce comm latency due to bridge
Serial1.begin(9600); //MEGA Serial1 connection. Should match your printer baud rate (dont forget the TTL to RS232 converter!)
Serial2.begin(9600); //MEGA Serial2 connection. Should match your printer baud rate (dont forget the TTL to RS232 converter!)
}
void loop() {
if (Serial1.available()) { // If anything comes though Serial1 (TX1/RX1),
c = Serial.read(); // read it
Serial2.write(c); //send it out Serial2 (TX2/RX2)
//Send it also out to Serial (USB) for viewing on Serial monitor
Serial.print("1: ");
Serial.println(c,HEX);
}
if (Serial2.available()) { // If anything comes though Serial2 (TX2/RX2),
c = Serial2.read(); // read it
Serial1.write(c); //send it out Serial1 (TX1/RX1)
//Send it also out to Serial (USB) for viewing on Serial monitor
Serial.print("2: ");
Serial.println(c,HEX);
}
}
If the aim is learning, then connect the Arduino UNO with a second USB Port of PC using a Soft Serial UART Port (Fig-1), a TTL <----->RS232 Converter (Fig-1),
RS232<------>USB converter cable (Fig-1).
