I would like to send strings to a weetech 25-pin serial port, simulating a barcode reading gun. i tried to use softwareSerial but it didn't work. how can I do? do i use rs232? I use a USB and then suitable?
If this is a classic RS232 serial port, you need a TTL to RS232 voltage level converter, like this one.
Of course, you also have to use the correct wiring, and send the correct data.
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Are you simulating it using an Arduino(I hope so), or using a PC and terminal software, for example?
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In order to simulate a thing, you first need to find out exactly what that thing does.
So you will need to find out what, exactly, this gun sends - including whether it uses RS232.
You will also have to find out if it depends on anything coming from the PC.
You could start by using a serial terminal to monitor what the the gun sends, and if anything is sent to it - be sure to use something that will show you all control codes, any binary data, etc ...
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I bought this rs232 shield, it arrives tomorrow,
today I tried sending data directly from arduino to db25 or using a TTL usb shield from arduino and an adapter from usb db9 and then a cable that connects to db25.
I used the following sketch:
/*
https://tecnicamente.wordpress.com/2012/04/07/arduino-max232-e-comunicazione-seriale-parte-1/
*/
#include <SoftwareSerial.h>
SoftwareSerial SSerial(11, 12); //12 RX e 11 TX
void setup() {
Serial.begin(9600);
while(!Serial) {}
Serial.println("ok");
SSerial.begin(9600);
}
void loop() {
if (SSerial.available()){
Serial.write(SSerial.read());
}
if (Serial.available()){
SSerial.write(Serial.read());
}
}
Today without rs232 shield it was not sending anything, maybe I am making a mistake in writing the sketch.
Looking at the library manual now, I have not declared the pinMode output input, can this affect it?
pinMode(rxPin, INPUT);
pinMode(txPin, OUTPUT);
This is the information of the device on which I have to connect with arduino to send strings to simulate the barcode reader.
So it tells you that it has three serial ports all on a single DB25 connector - therefore that is not a standard RS232 connector!
So the first thing you're going to have to do is to make up a custom cable to correctly connect your Arduino to the appropriate serial port within that connector.
It does say that it's "RS232-compatible" - so that means your will need an RS232 transceiver between your Arduino and the system.
If you're not familiar with these terms, then study this tutorial:
https://learn.sparkfun.com/tutorials/serial-communication/all
Your image also shows that RTS and CTS are present - so you'll need to find out if they are optional, or need some configuration, etc ...
The text refers to "Serial IN/OUT", but that does not appear in the table - which has only "Special input".
Is that a typo - who knows?!
It also doesn't describe how this "Serial IN/OUT (bidirectional)" is intended to work - so you have more digging to do on that.
And it tells you nothing at all about what it is expecting to receive on those ports - baud rates, parity, data format, etc, etc ...
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Again, do you have a working barcode reader to analyse?
I have a barcode reader with db9 output, I tried to read the output of the reader by connecting on pin 2 and 3. It works, I was able to get output, it corresponds to a println()
Thank you for your valuable help and the links. The datasheet is not very detailed, which is why I am going by trial and error.
Knowing that from the gun came out output from pin 2 and 3 using an adapter from 25db to 9 db I sent on those pins the sting without using the rs232 shield. But I got no reaction from the device.
I also tried connecting the 25db directly to pin 2 and 3, but again no reaction from the device.
You mean DE9?
Anyhow, have you successfully got that reader to work with this "weetech" serial port?
I meant de9, sorry for the mistake.
yes, I managed to make that reader work with weetech, but my intention is to be able to simulate it with Arduino and send the strings myself
Right: so that's the first step! Now you have something to simulate.
SO you need to spend some time to understand what that reader is actually sending - and anything that the Weetech sends back - and make sure that your Arduino faithfully matches that.
Start by monitoring the communications between the reader and the Weetech - you can do this using a terminal emulator (or two):
https://www.avrfreaks.net/s/topic/a5C3l000000UYWbEAO/t146507?comment=P-1422786
Also pay attention to the wiring.
Thanks for the advice, I will start to try and read the outputs with the programmes mentioned in the link you sent me.
As soon as I have news I will share it here!
Thanks!
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