maxrs232 softwareserial never detected

Projects Interfacing w/ Software on the Computer
1

I have attached a maxrs232 board to my Uno, hooked it up as follows:
Uno RX pin (10) - maxrs232 TX
Uno TX pin (11) - maxrs232 RX
Gnd/3.3v

#include <SoftwareSerial.h>
SoftwareSerial softSerial(10, 11); // RX, TX

void setup()
{
softSerial.begin(4800);
}

void loop()
{
if (softSerial.available()) {
Serial.println("Soft Serial available");
}
}

But available() never becomes true.

2

have you tried switching the lines?
can you post a datasheet of the - maxrs232 board -
which version of the IDE do you use?
which version of software Serial?

3

Change baudrate to,9600.
just do this

#include <SoftwareSerial.h>
SoftwareSerial softSerial(10, 11); // RX, TX

void setup()
{
 softSerial.begin(9600);
}

void loop()
{
  softSerial.println("hello");
delay(1000);
}
4

Thanks both of you for the reply. Had to change the rx/tx lines on the maxrs232 (pins incorrectly labelled) and set the baudrate to 9600. After that, maxrs232 is detected.

However, when I connect a cable up to the maxrs232 and use the read() command, it only returns a value of 255.

5

Google does not know what a maxrs232 board is - you must not have the name exactly right - post a link to the datasheet of your device.

My undersatanding is that a Max 232 is intended to bridge between a serial TTL connection and proper RS232 device.

You have not told us what is on the other side of your max 232 to send or receive data to/from the Arduino.

...R

6

Akubra:
Thanks both of you for the reply. Had to change the rx/tx lines on the maxrs232 (pins incorrectly labelled) and set the baudrate to 9600. After that, maxrs232 is detected.

However, when I connect a cable up to the maxrs232 and use the read() command, it only returns a value of 255.

255 means there is no data available. Use the Serial.available() function to get the amount of chars in the input buffer.

if (Serial.available() > 0) c = Serial.read();
else c = '';
7

All, sorry for the type: it is a max3232 board.

Board details in the following thread:
http://forum.arduino.cc/index.php?topic=266582.msg1879720#msg1879720

Thanks,
Mike