Multiserial Ports Identification

dayvidvictor · 12-17-2010, 11:47 AM

Hello everybody.
I'm writting an app for desktop and embedded linux and I need to get information about the multiserial port, and I need to know which port is been used (by a printer, por example).

The multiserial I'm using is an Altera Corporation Device 0004, and I just need to tell how many ports are there and how many is been used.

any ideas?

PS: I know if the multiserial is there by lspci, and to know the information I need I'm thinking about using setserial, but I'm having some trouble to do that.

michaelk · 12-18-2010, 07:31 AM

There is no standard protocol so trying to automatically identify devices attached to a serial port will be difficult.

dayvidvictor · 12-19-2010, 07:48 AM

Tks for the post Michaelk, but I don't need to identify the devices, I just need to know
how many of those ports are conected to something ...
The output of the program would be something like:

You Have an an Altera Corporation Device 0004
Total Ports: 4
Ports Conected to any device: 3
Ports Avaliable: 1
--

ya see, I think it's pretty much easy than the know what is the device conected.
tks

michaelk · 12-20-2010, 07:22 AM

Again it depends on the hardware. For devices that use hardware flow control you could check for the status of the CTS,DSR, DCD or RI signals. However, there are special serial cables that have hardware loopback for flow control on the PC side so this method not work. I do not know if you can check the status of the RX or TX signals if the device is not continuously sending data. So for devices that may only use the min number of wires i.e. TX,RX and GND not sure if there is any method to detect the device.