Searching \ for '[OT]: LCD 14-pin 2x7 pinout ?' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: www.piclist.com/techref/lcds.htm?key=lcd
Search entire site for: 'LCD 14-pin 2x7 pinout ?'.

Exact match. Not showing close matches.
PICList Thread
'[OT]: LCD 14-pin 2x7 pinout ?'
2001\10\19@193624 by Peter L. Peres

picon face
Hi,

I have a standard ascii LCD display with two lines, backlit etc, with the
14 pin 2x7 connector (for cables). The LCD board has pins 1 and 14 marked.
This is not very usefull since I do not know for sure whether the pin
order is:

A)
1  2
3  4
5  6
7  8
9  10
11 12
13 14

or B)

1  8
2  9
3 10
4 11
5 12
6 13
7 14

Notice how pins 1 and 14 are in the same position in both cases ;-(. No I
cannot ask the manufacturer, I bought these in a shop.

If any1 can  shed some light on this, please do, tia,

Peter

PS: Is there a way to find out by measuring ? I tried comparative
measurement vs. gnd etc but nothing conclusive came of it. The controller
is epoxy splotch chip on board type so I can't check wires to pins.

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\10\19@194718 by Dale Botkin

flavicon
face
On Fri, 19 Oct 2001, Peter L. Peres wrote:

> I have a standard ascii LCD display with two lines, backlit etc, with the
> 14 pin 2x7 connector (for cables). The LCD board has pins 1 and 14 marked.
> This is not very usefull since I do not know for sure whether the pin
> order is:

C) None of the above.  Viewed from the back it's like this:

13  14
11  12
9   10
7   8
5   6
3   4
1   2

http://www.doc.ic.ac.uk/~ih/doc/lcd/interfac.html is where I found a
diagram, among other places.  I've verified it, yes.

Dale

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads


2001\10\20@072831 by Peter L. Peres

picon face
Dale, thank you for the pin-out but it looks exactly like my A) version
held upside down ? ;-).

Anyway, thanks,

Peter

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\10\20@082148 by Dale Botkin

flavicon
face
On Sat, 20 Oct 2001, Peter L. Peres wrote:

> Dale, thank you for the pin-out but it looks exactly like my A) version
> held upside down ? ;-).

Well...  yeah...  but if you connected the wires in that order you'd still
have a non-working display.

Dale

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\10\20@144224 by Dwayne Reid

flavicon
face
At 11:42 PM 10/19/01 +0200, Peter L. Peres wrote:
>Hi,
>
>I have a standard ascii LCD display with two lines, backlit etc, with the
>14 pin 2x7 connector (for cables). The LCD board has pins 1 and 14 marked.
>This is not very usefull since I do not know for sure whether the pin
>order is:
>
>A)
>1  2
>3  4
>5  6
>7  8
>9  10
>11 12
>13 14

Standard dual row headers use the pin order in (A) above.

dwayne



Dwayne Reid   <spam_OUTdwaynerTakeThisOuTspamplanet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax

Celebrating 17 years of Engineering Innovation (1984 - 2001)

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
commercial email nor is intended to solicit commercial email.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\10\20@165836 by Thomas McGahee

flavicon
face
Dwayne Reid said:
> >
> >A)
> >1  2
> >3  4
> >5  6
> >7  8
> >9  10
> >11 12
> >13 14
>
> Standard dual row headers use the pin order in (A) above.
>

While it is true that the standard pin identification
for a dual row header is as shown above, it is NOT the
proper order when the pins exit from the BACK of the board,
as they do on every LCD module that *I* have ever run across.

Because the LCD header is always coming out the BACK of the
LCD board, you can easily get confused when using a
standard ICD cable to connect the LCD to a standard ICD
header.

The pin numbering gets exchanged, and if you are not
aware of this, then you can easily mess up the wiring on
your PIC board.

The problem occurs because one of the headers (LCD) is
actually mirror-imaged since it comes out the BACK of the
LCD board. If the PIC board ALSO had it's header coming
off the BOTTOM of it's board, then all would be OK.
But the PIC board normally has the header on the TOP of the
board.


Viewed from the BACK side of the LCD board, which is the side
where the pins stick out, it's like this:

13  14
11  12
9   10
7   8
5   6
3   4
1   2 *

or, if rotated it can look like

1  3  5  7  9  11 13

2  4  6  8  10 12 14
*

or

* 2   1
 4   3
 6   5
 8   7
 10  9
 12  11
 14  13

or

*
2  4  6  8  10 12 14

1  3  5  7  9  11 13

You will notice the (*) I placed next to pin (2) in each
of these diagrams. THAT is the pin that pin (1) of the
IDC CABLE connects to. This is a very important fact to
take note of, because most likely that IDC cable will then
connect to an IDC header on the board with the PIC, and
THAT will have its pins sticking up from the TOP of the
PIC board. The net result is that the pins end up getting
switched around as follows, when using a standard IDC cable:

LCD Header   IDC CABLE   PIC IDC header LCD FUNCTION
1            2           2              Vss (Gnd)
2            1           1              Vdd (+5)
3            4           4              Vo cobtrast adj.
4            3           3              RS
5            6           6              R/W
6            5           5              E
7            8           8              DB0
8            7           7              DB1
9            10          10             DB2
10           9           9              DB3
11           12          12             DB4
12           11          11             DB5
13           14          14             DB6
14           13          13             DB7

*********
What can you do if you have already messed up by having
your PIC board wired up the wrong way? Use TWO
identical IDC cables. Connect them together by using
two 7 pin rows of header pins, or if you don't have that
handy, then insert short lengths of snipped resistor
leads or #20 bare single strand wire into all 14 pins
of one cable end, and then plug the other cable into the
one with the wire pieces. Insert the two cables so that
the side with pins 1&2 plugs into the other cable's
side that has pins 1&2. This effectively re-routes the
wires so that LCD header pin 1 goes to PIC board header
pin 1, and the same with all the other wires.

Fr. Thomas McGahee


{Original Message removed}

2001\10\20@172015 by Dwayne Reid

flavicon
face
At 04:58 PM 10/20/01 -0400, Thomas McGahee wrote:
>Dwayne Reid said:
> > >
> > >A)
> > >1  2
> > >3  4
> > >5  6
> > >7  8
> > >9  10
> > >11 12
> > >13 14
> >
> > Standard dual row headers use the pin order in (A) above.
> >
>
>While it is true that the standard pin identification
>for a dual row header is as shown above, it is NOT the
>proper order when the pins exit from the BACK of the board,
>as they do on every LCD module that *I* have ever run across.

I agree with what you wrote but you are not answering the original
question: do the pin numbers increment horizontally (like above) or
vertically.  I assumed (from past postings) that Peter would take any
mirror problems into account because he already knows where pins 1 and 14
are on the display.

I don't mean to be confrontational - please accept my apologies if it comes
across that way.  Peter asked which of two possible pin numbering schemes
was correct given that he knew where pins 1 and 14 were.  The diagram above
is correct, given his location of those pins.

dwayne



Dwayne Reid   <.....dwaynerKILLspamspam@spam@planet.eon.net>
Trinity Electronics Systems Ltd    Edmonton, AB, CANADA
(780) 489-3199 voice          (780) 487-6397 fax

Celebrating 17 years of Engineering Innovation (1984 - 2001)

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
Do NOT send unsolicited commercial email to this email address.
This message neither grants consent to receive unsolicited
commercial email nor is intended to solicit commercial email.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics


2001\10\21@130646 by Thomas McGahee

flavicon
face
Well, kindly forgive me for giving too much information.
It is the teacher in me. I just KNOW that someone
out there is NOT aware of the mirroring problem
and is going to be in for a nasty suprise when they
non-chalantly connect and ICD cable up and their
LCD goes POOF because pins 1 and 2 are mirrored,
and happen to be the power pins.

The person asking the question is not the only person
reading the answers.

Just trying to be of help.
Fr. Thomas McGahee

{Original Message removed}

2001\10\21@131313 by Kevin Olalde

picon face
And I appreciate the help.  I've learned quite a bit from lurking and searching
the archives.

Thanks,
Kevin

Thomas McGahee wrote:
>
> Well, kindly forgive me for giving too much information.
> It is the teacher in me.
[snip]
>
> The person asking the question is not the only person
> reading the answers.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.


More... (looser matching)
- Last day of these posts
- In 2001 , 2002 only
- Today
- New search...