5V TLL to 5V USB to 12V RS232

Projects General Guidance
1

Hi All,

I have a peltier effect controller and I'm currently using a PC to control it. the controller has an RS232 input and I'm using a USB to RS232 cable to send the commands through the PC program to it.

I want to make the project more portable so I want to replace the PC with an Arduino.

I've found the datasheet that explains the message format for commands so all I need to do is send serial messages to the controller from the Arduino.

The way i see it I've got 2 routes:

  1. Get a MAX232 to level convert the the 5v TTL to +/-12V RS232 and put the output of the MAX232 into the input of my peltier.

  2. Break open my USB to RS232 cable and solder onto the input of the MAX232 inside there.

So really what I'm asking is which option makes the most sense / is option 2 even possible?

Cheers

Steve

Edit: Also as I send serial messages to the serial monitor on the PC using the Arduino's USB port, is it possible to use the USB port to send serial messages and then use a USB to RS232 cable to convert those into a signal for my controller?

2

Option 2 1[edit: Brain was thinking 1, fingers typed 2].
Get one of these
http://www.nkcelectronics.com/rs232-to-ttl-converter-board-33v232335.html
http://www.nkcelectronics.com/RS232-to-TTL-converter-board-DTE-with-Male-DB9-33V-to-5V_p_369.html
'328P only has 1 serial port. If you need to send data to a PC with it, then you need a different port to send data to your device. Look into Neosoftserial newsoftware serial, altsoftware serial, or get a 1284P board with 2 hardware serial ports.
I offer one with USB port and RS232 buffer for the 2nd port, with SD card and battery backed RTC also.
USB/Serial can be offboard or onboard, screw terminals are also an option.
http://www.crossroadsfencing.com/BobuinoRev17/

1045×620 115 KB

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3

Option 1; get a MAX232 board.

4
  1. Break open my USB to RS232 cable and solder onto the input of the MAX232 inside there.

Buy this module RS232 to TTL Converter and write your code.

5

Hi,

I have a peltier effect controller and I'm currently using a PC to control it. the controller has an RS232 input

Does it have any other input options?
Other than RS232?

Can you post a link to the controller please, or let us know the make and model of the controller.

Thanks, Tom... :slight_smile: