1 RS232
		    _________________________	     1	     Cable shield
25-pin D-type  14/ o o o o o o o o o o o o \25     2 TD    Transmit data
		 1/ o o o o o o o o o o o o o \13    3 RD    Receive data
		 '--|-|-|-------|--------------`    *4 RTS   Ready to send
For IBM PC,	   1|2|3|      7|g		    *5 CTS   Clear to send
link 4 to 5	    | | |	|r     * not used   *6 DSR   Data set ready
 and 7 to 20	   s|r|b|	|e       on VAX      7	     Signal ground
		   c|e|l|	|e		   *20 DTR   Data terminal ready
		   r|d|u|	|n
		   e| |e|   .---|---.		     1 DINP  Data input
		   e| | `----.	o 2  \		     2	     Signal ground
		   n| |   /   \       \		     3 DOUT  Data output
		    | `-----o  `----o  |	    *4 HINP  Handshake input
3/8-pin DIN	    |    | 1	     3 |	    *5 HOUT  Handshake output
		    |     \	      /		    *6 SINP  Status input
plugs viewed	    `------\	_    /		    *7 SOUT  Status out
from inside		    `--' `--'		 shell	     Cable shield
2 DECmate_printer
25-pin D-type   _________________________	     1	     Cable shield
		 14/ o o o o o o o o o o o o \25     2 TD    Transmit data
		 1/ o o o o o o o|o o o o o o \13    3 RD    Receive data
		 `-/--|-|---|-|-|-\------------'     5 CTS   Clear to send
		  /   | |   | | | |		     6 DSR   Data set ready
		  |   |_|_  | | | |		     7	     Signal ground
		  |     | | | |	| |		    20 DTR   Data terminal ready
DEC cable	  |     | |_|_|_; |		    
type BCC-05	  |     |/| | |   |
		  |     ||| | |   |
		  |   __|||_|_|	  |
9-pin D-type  | 9/ o|o|o|o|\6 |
		  | /1o|o o o o5\ |
plugs viewed  | `-||--------' |
from inside	  `---'`----------'
2 Pin_connections_and_names
The full RS232 (D-type) and S5/8 (DIN) pin names and connections are:

	RS232					S5/8
	-----					----
 1 PG   protective ground		  = shell	cable screen
 2 TD   transmit data		      =	1 DINP	data input
 3 RD   receive data		      =	3 DOUT	data output
 4 RTS  ready to send		      =	6 SINP	status input
 5 CTS  clear to send		      =	5 HOUT	handshake output
 6 DSR  data set ready		      =	7 SOUT	status output
 7 GND  signal ground		      =	2	signal ground
 8 DCD  data carrier detect
 9      -12V test level
10      +12V test level
11 QM   equaliser mode
12 SDCD secondary carrier detect
13 SCTS secondary clear to send
14 STD  secondary transmitted data
15 SCT  transmitter clock
16 SRD  secondary received data
17 SCR  receiver clock
18      initial local analogue loopback
19 STRS secondary request to send
20 DTR  data terminal ready		      =	4 HINP	handshake input
21 SQ   signal quality detector
22 RI   ring indicator
23      data signal rate selector
24 ETC  external transmitter clock
25      test indicator
