Pin D Serial Port Connection To Another Pc - Brainboxes CC-662 Hardware Manual

PCI Photon 8 Port RS232
and handshake requirements of both sides of your RS232
connection, the cross over cable becomes a matter of common
sense. The cross over cable is simply to ensure that the right
signals going out of one RS232 port go into the appropriate lines
of the other RS232 port.

9 Pin D Serial Port Connection To Another PC.

Suppose we want to connect the AT style 9 pin D Serial Port
to the serial port of another IBM PC 25 pin D. See Figure 6-3.
1) Connect the earth lines.
Line 5 of Serial Port 2 to lines 1 & 7 of the other PC.
This gives the two devices a common earth level.
2) Connect the Transmit and Receive lines together.
Line 3, TXD, Port 2 goes to line 3, RXD, of the other PC.
Line 2, RXD, Port 2 goes to line 2, TXD, of the other PC.
This allows each to receive the data transmitted by the
other.
3) Connect the Port 2 DTR line, pin 4 to the other PC DCD,
pin 8 and CTS, pin 5, lines.
Also, connect up the other PC DTR line, pin 20 to the Port
2 DCD, pin 1 and CTS, pin 8, lines.
This allows the receiving device to signal when it can no
longer accept data. The receiving device sets DTR false
when it is unable to receive any more data. The sending
device reads DTR on its CTS and DCD pins. It should stop
sending when CTS goes false.
4) Connect the Port 2 RTS line, pin 7, to the other PC DSR
line, pin 6.
Also, connect the other PC RTS line, pin 4, to the Port 2
DSR line, pin 6. This RTS line is used to let the other
device know that it is ready for data exchange.
Index
Chapter 4 Page 41