how determine type unknown connection?

[mohammad2050]

hi
I have a device that has a communication port but I do not know which type of connection.
I've measured the voltages on pins , that The following values were obtained :


in your opinion , this is which connection??how can determine type connection ?
in The manufacturer's catalog Been picture following :


Also come in the catalog the following descriptions :

 

[Harald Kapp]

Welcome to electronicspoint.

Obviously this is an RS232 connection using a special MIL-style connector.

 

[mohammad2050]

Welcome to electronicspoint.

Obviously this is an RS232 connection using a special MIL-style connector.

hi Harald Kapp ,
why rs232 ?! Here is 3.5 volt on pin in idle time while reach to 12 volt in rs232 ,
transducer is used for convert to RS232 , As has been said in the catalog

 

[BobK]

RS232 signaling voltage are specified as +-3 to +-15, so 3.5V is a valid signal level.

Bob

 

[mohammad2050]

RS232 signaling voltage are specified as +-3 to +-15, so 3.5V is a valid signal level.

Bob

Of course , but this voltage is in idle time and this voltage Becomes 0 to 2v or 3.5 to 5 v in run time

 

[BobK]

That sounds like TTL levels then. You would need something like a MAX232 to convert them to RS232.

Bob

 

[mohammad2050]

Excuse me Bob , My previous post is incorrect
I get below voltage in run time on each pin :
top and bottom pin are nearly 3.5 volt and Remain at the same level when pc and device exchange data together .
left pin become nearly -4.92 volt in connect time and change when pc and device exchange data together (for example become -0.8 or -2.3 or -3.2 and then return to -4.92 when pc and device do not exchange data together )
and voltages after Manufacturer Transducer are following :
voltage on rxd pin is -4.9 volt in connect time and Remain at the same level when pc and device exchange data together .
voltage on txd pin is -2.9 volt in connect time and change when pc and device exchange data together (for example become 2.4 or 1.8 or -0.4 and then return to -2.9 when pc and device do not exchange data together )

 

[BobK]

Okay then, It does sound like RS232.

It sounds like you are successfully exchanging data then, is this correct?

Bob

 

[mohammad2050]

yes i can exchanging data between device and pc but do not understand What do Transducer ؟؟
before Transducer(on device pin) voltages are following :
top and bottom pin are nearly 3.5 volt and Remain at the same level when pc and device exchange data together .
left pin become nearly -4.92 volt in connect time and change when pc and device exchange data together (for example become -0.8 or -2.3 or -3.2 and then return to -4.92 when pc and device do not exchange data together )
and voltages after Manufacturer Transducer(on 9 pin male So that 9 pin female is connect to pc) are following :
voltage on rxd pin is -4.9 volt in connect time and Remain at the same level when pc and device exchange data together .
voltage on txd pin is -2.9 volt in connect time and change when pc and device exchange data together (for example become 2.4 or 1.8 or -0.4 and then return to -2.9 when pc and device do not exchange data together )

 

[BobK]

I presume you are measuring with a multimeter. The signals are changing rapidly and the multimeter cannot follow them. You will get something like the average voltage over the time the multimeter is sampling. If you want to really see what is going on, you need an oscilloscope or logic analyzer.

Bob