date 19.12.2000
To: phk@freebsd._ERASE_.org
Subject: plip cables
From: "Julian Stacey" <jhs@
Organization: Vector Systems Ltd - Munich Unix & Internet consultancy
X-Web: http://www.berklix.com/~jhs/

Hi Poul-Henning,
I suggest maybe add a sentence to src/sys/dev/ppbus/if_plip.c ?
Something like:
 Caution: There are presumably at least 2 types of parallel cable
 available for purchase: buy/build the right one !

I append background info (not suggesting apply mammoth diff, too big,
just that's my notes format, & so you can see my source):

# This is a shell archive.  Save it in a file, remove anything before
# this line, and then unpack it by entering "sh file".  Note, it may
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#	if_plip.c.diff
#	ms-win.html

*** 4.2-RELEASE/src/sys/dev/ppbus/if_plip.c	Wed May 24 02:20:57 2000
--- jhs/src/sys/dev/ppbus/if_plip.c	Tue Dec 19 18:28:56 2000
***************
*** 65,70 ****
--- 65,119 ----
   *	|GND	18-25	18-25	GND	-        |
   *      +----------------------------------------+
   *
+  * Caution: There are presumably at least 2 types of parallel cable 
+  * available for purchase in the computer industry, as jhs@ read
+  * the following quote off the web page of a company that sells parallel 
+  * cables, this particular company being the one whose web reference is
+  * embededded into MS-Win-98, when you click down from "Start" through
+  * "Direct Cable Connection"
+  * Quote:
+  *	Blazing Speed: The DirectParallel(R) Universal Fast Cable
+  *	transfers data at speeds comparable to typical LAN
+  *	connections. The DirectParallel(R) Basic 4-Bit Cable
+  *	provides slower date transfer rates than the
+  *	Universal Fast Cable. 
+  *	....
+  *	WHAT ARE THE DIFFERENCES BETWEEN THE DIRECTPARALLEL(R) UNIVERSAL FAST
+  *	AND BASIC 4-BIT CABLES?
+  *	The DirectParallel(R) Universal Fast Cable provides the
+  *	highest speed connections across the full spectrum of
+  *	available parallel ports automatically. This cable
+  *	has intelligent circuitry built into it that
+  *	automatically identifies the parallel port of each
+  *	computer and will optimize the data communications
+  *	for the fastest possible speeds between the two
+  *	computers. The intelligent circuitry is powered by
+  *	the computer - so, no separate battery or AC adapter
+  *	power source is required. The maximum burst transfer
+  *	data rate and maximum effective continuous transfer
+  *	rate for this cable are up to 500 KBytesper second
+  *	respectively. 
+  *	
+  *	The DirectParallel(R) Basic Cable is an economical
+  *	slower version of the Universal Fast Cable. The
+  *	maximum burst transfer data rate and maximum
+  *	effective continuous transfer rate for this cable are
+  *	up to about 70K bytes per second. 
+  *	
+  *	So, connections between computers using the
+  *	DirectParallel(R) Universal cable can be up to 10 times
+  *	faster than the Basic Cable and only the Universal
+  *	cable optimizes the connection to take advantage of
+  *	high speed EPP and ECP parallel ports. 
+  *	
+  *	Of course, data transfer rates are dependent upon PC
+  *	type, CPU speed, parallel port type, data
+  *	compressibility, Windows 95/98/2000, and other
+  *	protocol overhead. Windows 95/98/2000 typically uses
+  *	data compression when using Direct Cable Connect -
+  *	therefore highly compressible files will transfer the
+  *	fastest. 
+  *
   * Expect transfer-rates up to 75 kbyte/sec.
   *
   * If GCC could correctly grok
---------------
Phillip says to connect a WIn95 to a Win98, need to an IPX/SPX protocol stack
on the Win98 end then use Direct Connection 
(so maybe 98 might be other EG TCP/IP ? maybe)
Also need to name the computers with Control Panel, Network, Identification.