If I remember correctly (and I might not) the TIL311 is a smart LED, with a
4 character addressable latch.  I think these devices were actually 15
segment devices, allowing display of the complete ASCII set.  The logic
circuits are 5V TTL.  I will check at home to see if I still have info on
these useful, but way expensive devices.


CIAO - Martin R. Green
elimar@bigfoot.com

----------
From:   Jacques Vrey[SMTP:jvrey@IT.NEW.ISCORLTD.CO.ZA]
Sent:   Wednesday, September 10, 1997 4:30 AM
To:     PICLIST@mitvma.mit.edu
Subject:        Re: [OT] 7 Segment LED

>
> Hi,
>
>    Sorry I don't have a diagram for you, but I have a suggestion.
>
> Have you tried putting one of them in a breadboard, and using a 3V supply
> and a 200R resistor to check out the pins. Connect a random pin to ground
> then connect each pin in turn through the resistor to +3V.
>
> These are the possible outcomes.
>
> Common cathode, gnd not connected to cathode - no segments light up.
Connect
> +ve through resistor to pin and probe for cathode.
>
> Common cathode, gnd connected to cathode - lots of segments light up in
turn
> (bingo) start writing down pin allocations.
>
> Common anode, gnd connected to anode - no segments light up. Connect +ve
> through resistor to pin and start writing down segmemnts.
>
> Common anode, gnd connected to segment - only one segment lights up.
Connect
> +ve to pin which lights segments and start writing down pin allocations.
>
> There may be some pins which are not connected, or which are bridged
> together. If you have a meter in series with the 3V supply it's easy to
see
> which ones these are.
>
> Hope this is some help,
>
>                         Keith.
> ------------------------------------------------------------
> Keith Dowsett         "Variables won't; constants aren't."
>
> E-mail: kdowsett@rpms.ac.uk  or kdowsett@geocities.com
>
> WWW: http://kd.rpms.ac.uk/index.htm
>      http://www.geocities.com/CapeCanaveral/Lab/8979
>
>
Hi there..again

In response..
That was the first thing I tried and all I managed to locate was the
dp's.
This 7seg has a small chip in it that appears to do some decoding as
each segment actually consists of four individual LED's as such:

+--\/----\/--+   +------------+
|            | 14|0          0|1
|  o o o o   |   |            |
|  o     o   | 13|0          0|2
|  o     o   |   |      T     |
|  o o o o   | 12|0     I    0|3
|  o     o   |   |      L     |
|  o     o   |   |      3    0|4
|o o o o o o |   |      1     |
|            | 10|0     1    0|5
|   +---+    |   |            |
|   |IC |    |   |            |
|   |   |    |   |            |
|   +---+    |  8|0          0|7
+-----/\-----+   +------------+

Maybe this will shed some light on the problem.
Thanks anyway.
Regards
Jacques Vrey
Iscor Steel Profile Products
Newcastle
South Africa
Tel: +27 (0)3431 48759
jvrey@it.new.iscorltd.co.za