On April 15, 2011 at 00:17, jimmypopali69 said...
Heres the crash course I give ALL my techs on how to terminate rs232, but we always do custom solder ends on boths sides
-Terminate one side
That's connect the wires to the pins, right?
-On other side connect grounds
Grounds only? I ask because there's usually one ground.
-check the pins on the wire you just terminated for voltage, one will have between -4 and -11 volts checking from gnd to the other 2 pins, lets call this Line A, we will call the other line B
Whoa. I'm holding wires connected to a DB9 in my hand, and it'g got voltage on it. Did you mean, for this test, for me to connect it to the device it will be connected to?
Whoa again.
One will have voltage checking from ground to the other
two. This means one will have voltage from ground, the other won't have voltage, right?
-check the unterminated side from gnd(p5) to the other 2 pins (2)(3), one will have voltage between -4 and -11 volts, call this pin B, other other pin we will call pin A
Whoa again. If I'm checking the unterminated side, then I haven't connected wires to the pins yet, and you want me to check the voltage on the pins. Did you forget to tell me to plug the connectors in on both ends?
-terminate line A to pin a
-terminate line b to pin b
Perfect connections every time, no need to check pinouts**
very rarely neither line will have voltage, check settings to make sure serial is enabled, if it is, you need to check specs on that device, it will say a line is TX, just assume that pin has voltage, and continue as above.
Can we simplify this a bit by saying that we use pin 5 for ground, and we work it out so that pin 2 on one end goes to pin 3 on the other end; another way to say it is that the wire with voltage coming from the far end goes to the pin that doesn't have voltage on the near end.
As for color code, this can't be defined because the colors on pins 2 and 3 on one end are reversed on the other end.
