RS232 voltage levels

I read on the documents page (UART) the following:

I want to use a sensor ( and the manufacturer offers a RS232 (0 to 10V) interface. This is the way it is written in the datasheet: RS232 (0…10V). So 0° are 0V and 360° are 10V.

I want to ask you If I can use the RS232 Module from GHI ( so that I can convert these 0-10V to TTL with the help of this module. WIll this work? Will the module work with this range of the Sensor’s output: 0 to 10V? Would I have to change the voltage level or do something else?

Thank you!

Page 9 and on of the RS232 manual talks about this.

Basically, a UART is a serial communication stream, and it is not an “analog out” signal that says 0v=0 degrees, 10v=359deg. I think there IS an analog out on the device if you wanted to use it but my suggestion is just keep using the RS232 serial information from it.

RS232 is a standard that has some reasonably relaxed tolerances, so the RS232 interface on the inclinometer and the RS232 module won’t have a problem communicating.

Thanks Brett. Could you give a link to this manual, I really do not know which manual you are talking about. Thank you.

I found it via the link you gave me :slight_smile:

Right hand side are some downloads listed there, one of them explicitly says RS232 manual

Thanks Brett. As you say, I hope that I will have no problems using this sensor. What about this one:

Could you take a look at it? What should I use to read the sensor’s output? It is an incremental sensor and it ouputs some signal waves. Could I use the RS232 Module?

@ Teodor17 - That looks like a standard quadrature encoder output signal, with an A and B phase as well as an Index signal you can use to count complete revolutions. Each of these signals also has an inverted version (opposite polarity voltage).

This is not an RS232 signal. You will need to determine what the maximum positive voltages are, and if they are 5V or less you may be able to feed them directly into your microcontroller and do some pulse-counting.

@ Iggmoe: Thank you for your helpful reply. According to the datasheet of the product ( the levels of the signal are between 2.5 V and less than 0.8 V (see attached picture). So, there are signals A, not A, B, not B,I,R, not I, not R. Which of these signals do I need so that I can decode the angle?

Do I have to use the PinCapture ( Could you provide suggestions on how to wire this up with the FEZ Spider? I would be grateful!

the range of voltages just means that it will record correctly as high & low signals on an input pin of a 3.3v micro. It will not need you to connect it to an RS232 module for that type of signal.

You’ve pointed out a number of devices. What are you using to decide what to choose, or do you have all these devices?