Re: HowTo gpio with com-port?

[Per-Erik Persson]

I spent some time trying to toggle the pins in the serial port in 
various ways.
The easiest way for me was to install pyserial and to control the pins 
in python takes only two or three lines of code.

This is neat if you just want to do some basic stuff.


Jan Klemkow wrote:

Hello,

I want to get some signals from a electronic circuit at my serial-port 
com0. I don't know how to attach the pin's from the serial port with 
the gpioctl tool. I think it my hardware is not supported, but I don't 
know exactly. In my dmesg there is nothing like this:


Please consider the environment before printing this email

Re: HowTo gpio with com-port?

[Marc Balmer]

Jan,

I want to get some signals from a electronic circuit at my serial- 
port com0. I don't know how to attach the pin's from the serial port  
with the gpioctl tool. I think it my hardware is not supported, but  
I don't know exactly. In my dmesg there is nothing like this:


"gpio0 at gscpcib0: 64 pins"

What could I do to get the signals from my circuit or to get support  
with gpio?


I am sorry, but doing this with the gpio framework is not possible.   
To make this
happen, it would require a small driver that wins over the standard  
serial port
driver during system auto configuration and that provides the modem  
control lines
as GPIO.  While I think such a driver would be fairly easy to write,  
it does not yet

exist to my best knowledge.

You can, however, open the serial port's tty device and query the  
modem control

signals.

- Marc Balmer

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