Re: misc/40641 (Serial port docs show pinout backwards)

[Martin Husemann <martin%duskware.de@localhost>]

The following reply was made to PR misc/40641; it has been noted by GNATS.

From: Martin Husemann <martin%duskware.de@localhost>
To: Ben Wong <ben%wongs.net@localhost>
Cc: gnats-bugs%netbsd.org@localhost
Subject: Re: misc/40641 (Serial port docs show pinout backwards)
Date: Tue, 30 May 2023 12:10:05 +0200

 On Mon, May 29, 2023 at 03:37:28PM -0700, Ben Wong wrote:
 
 > Circular 8         Signal            DB-9
 >     1           HSKo (+12V)           6
 >     2           HSKi                  7
 >     3           TXD-                  5
 >     4           GND                   3,1*
 >     5           RXD-                  9
 >     6           TXD+                  4
 >     7           No Wire
 >     8           RXD+                  8
 > 
 > * Pins 1 and 3 on the DB-9 end are jumpered together.
 > 
 > The pins on the male end of the circular 8 connector are numbered as shown:
 > 
 >           6 7 8
 >          3 4   5
 >            1 2
 
 I just checked my working powermac G5 console cable and I can confirm
 that looking from the outside onto the pins of the male 8 pin connector
 it looks exactly like in the NetBSD documentation page:
 
    8 7 6
   5   4 3
     2 1
 
 and I think the Apple shema shows the pins on the inside of the connector
 (the soldering side). I also confirmed that pin 4 of the cirular 8 pin
 jack is connected to GND at pin 5 of the DB9.
 
 Since this connector is asymetric the numbering is pretty clear (while
 the DB9 side is harder to get right, but there are typicaly numbers on
 the soldering side).
 
 The numbering for the male DB25 and DB9 connectors on the NetBSD page
 are from the same point of view, i.e. if you solder a male DB25 and have
 it lying on a desk before you with the shorter row pointing towards you,
 pin 25 is in the lower left corner, while pin 1 is on the upper right edge -
 but the image on the NetBSD page shows the view onto the connector when
 the cable is finished (and you can't see the soldering side).
 
 So maybe the page should get a additional hint to clarify the direction
 we are looking at the pins, but otherwise it seems to be correct to me.
 
 Martin