🚀 go-pugleaf

In article <4bfka8$ffa@grid.direct.ca>, gary kaiway <gkaiway@direct.ca> wrote:
>In article <pumaDJKy87.7F6@netcom.com>, puma@netcom.com says...
>
>>>>>Is there a way to get two modems talking directly to each other,
>>>>>instead of over a dialup line?
>>
>>While this works, in most cases you can achieve faster speeds and 
>better
>>handshaking by connecting the two system's serial ports with a 
>null-modem
>>cable.  
>
>Does anyone happen to know how to make a null-modem cable?  (25pin to 
>25pin.)  I'm in the process of trying to fix one, and need to know 
>which pins to swap.
>



The easiest solution, if you don't need status lines, is...
	Trans	2 --> 3	Receive
	Recv	3 <-- 2	Transmit
	Gnd	7 --- 7	Gnd

If you want to tie the status lines high on each end, and
not use any more wires in the cable...  Do the same as above
and then on each end connect
	DTR (term ready) 20 --> 6 Carrier detect DCD
			      & 8 Dataset ready  DSR

	RTS (req to snd) 4 --> 5 Clr to send    CTS
These connections are within the connector on BOTH ends,
and do not go end-to-end.


If you want to actually pass the status lines end-to-end,
do the same but from one end to the other, like so

		2 --> 3		TX RX
		3 <-- 2		RX TX
		7 --- 7		G  G
	       20 --> 6 & 8	DTR - DCD & DSR
            6 & 8 <-- 20	DCD & DSR - DTR
		4 --> 5		RTS CTS
		5 <-- 4		CTS RTS

This is how most commercial null modem cables are made.


-- 
puma@netcom.com