I have tried every thing i can draw from the tutorials of to get a dm13a breakout to work... No joy. I have read, reread, and reread again every info page and drawing on how to wire the leds. common + to all leds work with ground individually. I may not understand the electronic symbols used (noob). Not sure what ENA means. I have tried to join all grounds. Tried 2 different power sources (5v) with and without combining grounds. not sure what else to try. I started with all direct wiring of annunciators and started building my sim based on multiple megas... now they are obsolete based on new plans.
Nov 13, 2019 in LEDs, Digital Output by

2 Answers

Hi LesGilmer,

see here:

The "S" line of the DM13A is your controller PIN, not the "S" BUS.

To use a common low-power LED, simply connect it to the pin (anode) and to the ground bus (cathode) using a series resistor that can vary from 100 Ω to 1 kΩ depending on the indicator brighntess you need.



Nov 14, 2019 by
Thanks for the reply... However this gives me no new information. I had studied both of the links already. As I said, Each Led works when tested individually. Hoping for more helpful information.
Hi Les, Me also, I tried everything I understood but to no avail. In the meantime, I might have messed up my Mega board. That's for another time, another thread. I'll be watching for a hint.


Please read this page (if you didn't yet): http://simvim.com/tech_dout.html  - all is simple and clear.

Make all as described. And about the ENA  (chip enable) signal  you can read on the picture  too..

ALso  see this topic.


Nov 16, 2019 by