[mythtv-users] I'm about to give up on this entire thing...

Tue Jun 10 01:20:08 EDT 2003

Ok, I'm very close to giving up on this entire project.

I am SOOO frustrated right now it's not even funny.

Now, even when I only connect the TxD and Gnd, my receiver keeps turning
itself on and off.

----- Original Message ----- 
From: "John Klimek" <jmk396 at psu.edu>
To: "Discussion about mythtv" <mythtv-users at snowman.net>
Sent: Monday, June 09, 2003 11:30 PM
Subject: Re: [mythtv-users] DirecTV (RS232-to-RJ11 cable) -- I think
Ifigured out my problem!

> Ok, here are my findings so far.
>
> DB9F pin assignment is definitely as follows:
> 5 4 3 2 1
>  9 8 7 6
>
> RJ22 pin assignment seems to (definitely?) follow:  (when looking at the
> bottom, pin-side)
> Pin-1
> Pin-2
> Pin-3
> Pin-4
>
> Following the pin assignment, I've connected:
> (RJ22-to-DB9F)
> 1 - to - 5  [ground]
> 2 - to - 2  [receive]
> 4 - to - 3  [transmit]
>
> Here is what happens:
>
> 1)  If I DO NOT connect the RECEIVE line (2 - to - 2), I can transmit to
the
> receiver PERFECTLY.  The receive changes channels, etc, etc and works
> perfectly fine.  Of course I still get "a Timeout" response from the
receive
> because the RxD line is not connected.  However it will still change
> channels.
>
> 2)  If I DO NOT connect BOTH the RECEIVE and the GROUND line, whenever I
> transmit to the receive it will change to WEIRD channels and do weird
> things.
>
> 3)  If I connect ALL THE WIRES, as soon as I plug the cable into the
> computer and the receive, my satellite receiver will turn itself on and
off
> constantly.
>
> I believe my problem is DEFINITELY located in the receive line.
>
> If I can transmit fine (with TxD and Gnd connected only), then I think its
> safe to assume my RJ22 and DB9F pin assignments (and connections) are
> definitely correct.  However once I hookup the RxD line, I immediately get
> problems ranging from receiver self shutdown/reboot or I get "Timeout"'s
> when I send
>
> Also, I measured my cable and it's 50' (I thought it looked longer than
> that).  So, if I can transmit fine then I'm thinking I have one of two
> possible problems:
>
> 1)  The satellite receiver is not strong enough to send a signal back to
the
> computer over the 50' of cable.  Can I test for this any easy way?  It's
> hard to rewire my cables espicially if I had to chop the length back down.
>
> or
>
> 2)  The diagram is screwed up and I'm actually suppoed to connect RJ22 Pin
3
> to DB9F Pin 2.
>
> Has anybody else built a cable like this that can possibly help?
>
> Ray, thank you so much for helping me.  If you have any other ideas please
> let me know.  I know I'm very to getting this to work.
>
> Thanks!
>
>
>
> [entire original message thread follows]
> > First, please do not apologize for "being long". Troubleshooting cabling
> > problems is always a matter of detail, and I'd much prefer to wade
through
> > some irrelevancy than to hit "I think I got that part right" in the
middle
> > of a report. And in facf none of the detail you provide is irrelevant,
> anyway.
> >
>
> Thank you very much.
>
>
>
> > At 08:39 PM 6/9/2003 -0400, John Klimek wrote:
> >
> > >http://www.pcmx.net/dtvcon/ -- this is the diagram that I tried to
> follow.
> > >
> > >If you turn the phone connector (RJ22) upside (so you can see the gold
> > >pins), I ordered them like this (top to bottom):
> > >
> > >1 (white)
> > >2 (white)
> > >3 (red)
> > >4 (black)
> >
> > In looking at the URL, I can't really see which way they expect you to
> > orient the RJ22 connector. Were I to guess, I'd make the same guess you
> did
> > ... but that still eaves it a guess, albeit a shared one.
> >
> > >Then, I cut a 75' (I think its 75', it appears longer than 50')  RJ11
> cable
> > >just to make my RJ22 cable longer.  Now, I connected these two cables
> like
> > >this:
> > >
> > >RJ22 --> RJ11
> > >1 - (white) --> Green
> > >2 - (red) --> Red
> > >3 - Not used
> > >4 - (black) --> Black
> >
> > Note that between these two descriptions, the location of the (red) wire
> > moved from position 3 to position 2. Is this just a typo or does it
> reflect
> > a wiring error?
> >
> > If it is a wiring error ... as I read the wiring diagram at te URL you
> > reference, this is the pin for RX (that is, the line the PC receives
data
> > on). Miswiring it would cause replies from the DirecTV device not to
reach
> > the PC, no matter how you wired the DE9 end.
> >
> >
> > >Now, I cut an older cable that was used to connected an external modem
to
> a
> > >desktop.  One end was DB25M and the other was DB9F.  I cut off the
9-pin
> > >female connector.  It has 9 pins which are holes (I'm assuming this
means
> > >DB9F).
> > >
> > >Following the diagram, I connected as follows:
> > >
> > >RJ11 --> DB9F
> > >1 - (white) --> 5 (Brown)
> > >2 - (red) --> 2 (Red)
> > >4 - (black) --> 3 (Orange)
> >
> > Another notation problem. Pin 1 on the RJ11 (above) was Green, not
> (white).
> > This time, though, I assume you are just still using the RJ22 color
codes,
> > not making a wiring error.
> >
> >
> > >I used a multimeter (to check continuity) to check which hole on the
DB9F
> > >connector went to which colored wire.
> > >
> > >Now, before I added my "extension" (RJ22 --> RJ11), I used these hole
> (pin?)
> > >assignments for the DB9F connector:
> > >
> > >5 4 3 2 1
> > >  9 8 7 6
> >
> > There are pins inside the holes, so I still call them pinouts. If you
are
> > viewing the connector from the "outside", this one is the right pinout
set
> > for a female connector.
> >
> > >The cable transmited, but DTVCON always gave a "Timeout" error when
> waiting
> > >for a response.
> > >
> > >Now, I tried reversing my DB9F hole assignments:
> > >
> > >1 2 3 4 5
> > >  6 7 8 9
> > >
> > >The cable transmits, but again recevies a "Timeout" from DTVCON.
> > >
> > >My "reversed" hole assignments I think I have confused with a DB9M
> > >connector.
> >
> > Me too.
> >
> >
> > >Sorry for this being so long but I'm trying to be as through as
possible
> so
> > >you could help me =)
> > >
> > >Thank you so much.
> > [old stuff deleted]
> >
> > _______________________________________________
> > mythtv-users mailing list
> > mythtv-users at snowman.net
> > http://lists.snowman.net/cgi-bin/mailman/listinfo/mythtv-users
> >
>
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