Serial Config help.

Perhaps this thread will help:

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1243894373

Good luck! Salvador

I`d looked at that earlier today, and the parts I could make sense of don`t address the Start Bit issue, that`s why I was even wondering if it was possible?

Have you written some experimental code and wired it up yet?

What was the printer originally designed to connect to? 

Can we assume the serial port on a PC?

it`s a PXP40 that goes on a PX1000 Telex machine, the connector is like a stereo earphone jack, no PC involvment per se.

as for test "code" I`v tried 3 different terminal progs, and non of them work as there`s no config for a start bit

the printer Does work however as I tried it on the PX1000.

see here: http://www.cryptomuseum.com/crypto/philips/px1000/index.htm

Have you looked at this page about RS-232 Serial or this page?

The PXP-40 Printer is similar to the Atari 800 40 Column Thermal Printer (early 1980s)  that I own.

Some systems use:  (image)

• base ring: ground (pin 5 of DB9)
• middle ring: serial output from Device1 to serial input of Device2 (pin 2 of DB9)
• tip of pin: serial output of Device2 to serial input of Device1 (pin 3 of DB9)

Have you been able to determine if it uses standard ASCII?

Adding a start bit should not be too difficult. 

You need to heed the warning about connecting 12 volt device to the i/o of the 5 volt arduino when using RS-232RS-232.

Soon you will be happily running this program on your repurposed thermal printer.

Have you looked at this page about RS-232 Serial or this page?

The PXP-40 Printer is similar to the Atari 800 40 Column Thermal Printer (early 1980s)  that I own.

Some systems use:  (image)

• base ring: ground (pin 5 of DB9)
• middle ring: serial output from Device1 to serial input of Device2 (pin 2 of DB9)
• tip of pin: serial output of Device2 to serial input of Device1 (pin 3 of DB9)

Have you been able to determine if it uses standard ASCII?

Adding a start bit should not be too difficult. 

You need to heed the warning about connecting 12 volt device to the i/o of the 5 volt arduino when using RS-232RS-232.

Soon you will be happily running this program on your repurposed thermal printer.

the 12v/5v thing isn`t an issue, I`v dealt with all that stuff before and simply use a cmos inverter, I`ll not be tapping the power anyway, just the GND and the Data (sleeve and tip), and the data is +/-5v capped.

I fully understand What it wants, I`v just no idea how to make an Arduino do it, and don`t really want to mess around building Parallel to Serial convertor out of 74xx series chips, and messing around with clock divisions for framing etc...

Happily the one "Normal" part about this is that it IS ASCII code, but that`s about where it ends.

it`s a nice little printer and I managed to save it`s life and change out the batteries before too much damage was done, and I think it would make a great addition to ZED.

the goal is have 8n1 serial IN and this crazy protocol come OUT of the arduino (same baud naturally), to drive it.

All right then, YT2095, my research on arduino.cc indicates that

#include "SoftwareSerial.h" would be a good beginning.

If you are using Arduino 1.0 then  this include is already part of 1.0

and the following are available:

Functions

• SoftwareSerial()
• available()
• begin()
• isListening()
• overflow()
• peek()
• read()
• print()
• println()
• listen()
• write()

SoftwareSerial is no different than useing the built in Serial port. I don't know of anything that even still uses the start bit. As far as I know, the serial port on an Arduino is only 3 wires, RX, TX, and Ground. So you won't be able to configure the flow control.

However I would sugest asking this on the Arduino Forums. if you haven't already.

agreed, I use this library on a few things, one of which is a printer ironically

I use the NewSoftSerial library, more or less the same as the above anyway, only I can`t see anywhere to config it with a Start bit and 7E2?

Have you tried casting the variable as a double?

Here is my idea:

Given an AsciiChar Byte which Serial.read() has provided from the Console:

NewChar = AsciiChar|0x80;  // set the first bit high so you have the "Start Bit"

DoubleChar = (NewChar * 4) + 3;  // shift the bit pattern left 2 positions and

// set the two low order bits high for the "Stop bits"

If softwareserial cannot handle the double, then break it into two bytes

and send them one after the other using myserial.write.

// On the other hand it seems that

myserial.print(NewChar + 0xc0);  // might get the job done too.

// this +  is a string concatination. 

I`ll give both of those ideas a shot tomorrow

just out of curiosity however, does anyone know what Endian the arduino sends it`s serial data?

another quirk of this printer is that it has to be little endian to work  *sigh*

Additional info:

We cannot trust what we see on the Serial Monitor.  (reference here)

Instead of the last line in the code above; I recommend trying the following:

mySerial.write(((double(Serial.read()| 0x80)) *4)+3);

or

mySerial.write((((double(Serial.read()| 0x80)) *4)+3)* 0x0010);

A really complete ASCII chart can be found here.

Okay, I don't know if this will work for you or not; it is just my theory.

If it does not work out then feel free to say so after

reporting your Serial Monitor test inputs and outputs from the PXP-40.

A screen capture and a clear photo of the thermal paper would be ideal.

Always remember to "Stay Calm and Carry On."

ok, here`s what I have so far:

#include <NewSoftSerial.h>

NewSoftSerial Thermal(2,3); // RX TX. only TX used

void setup()

{

   Serial.begin(9600);

   Serial.println("Enter text to be printed:"); 

   // set the data rate for the SoftwareSerial port

   Thermal.begin(1200);

    // UCSR0C = B00100100; <--doesn`t change anything?

}

void loop()

{

   if (Thermal.available())

     Serial.write(Thermal.read());

   if (Serial.available())

   // Thermal.write((((double(Serial.read()| 0x80)) *4)+3)* 0x0010); <--won`t compile

   // Thermal.write(((double(Serial.read()|0x80))*4)+3); <--won`t compile

     Thermal.print(Serial.read()|0x80);

}

using the above, I get "393636" printed as a result of typing in "hello world".

using the line(s):

mySerial.write(((double(Serial.read()| 0x80)) *4)+3);

or

mySerial.write((((double(Serial.read()| 0x80)) *4)+3)* 0x0010);

I get:

/newsoftserial.h71: error: 'virtual void

newsoftserial::write(uint8_t)' is private

_7e2test:20: error: within this context

so really I have no way to test if this will work or not?

I`ll keep going though

If your IDE is version 1.0, don't include NewSoftwareSerial. It is already in the IDE. so just include SoftwareSerial.

I use version 22 for almost everything, version one only really gets used if I program an ATtiny85.

22 has all my collection of libs and hardware tweeks, I`m of the mind that if it aint broken, don`t fix it, so I stick with 22.

anyway, my lunch break is over, so I`m trying with Thermal.Print instead of Write, it will at least compile then.

results later