What pins should I connect when performing a loop back test? Do all pins need to be connected?

For RS-232 serial devices: Connect TX to RX Connect RTS to CTS to RI Connect DTR to DCD to DSR For RS-422, RS-485 serial devices: Connect TX+ to RX+ and TX- to RX- Connect RTS+ to CTS+ and RTS- to CTS- For RS-530 serial devices: Connect TX+ to RX+ and TX- to RX- Connect RTS+ to CTS+ and RTS- to CTS- Connect DTR+ to DCD+ to DSR+ and DTR- to DCD- to DSR- Only the data pins (TX and RX) are necessary for a loop back test. Unless you need to test the modem control signals (RTS, CTS, DCD, DTR, DSR, and RI) there is no need to connect them. Please refer to your manual for the correct pin assignments for your serial device.

More.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.