Hi all, I have been working on modeling the Zibo 737-800. I’ve used many multiplexers (CD74HC4067) for my switches, buttons, etc... Prior to last week everything worked flawlessly until one day after some updates to SimVim, Zibo, and X-Plane my switches were unresponsive. Occasionally I would get a flicker among many switches at once but it was seldom. I also noticed the RX light on my Arduino Mega board was in a constant flashing state. I have since attempted to fix the problem by using older versions of the Zibo mod (when it did work) and I’ve even purchased new Arduino Mega boards only to find the same results. I took a multiplexer and connected it by itself with a singular input switch just to test and I got no results other than a flashing RX light. On the other hand, I’ve connected a switch directly to the Arduino Mega and it worked. The RX light continued to strobe though. When I connect the Arduino Mega to my computer via USB I get a green “on” light like normal. As soon as I select “Hardware Reconnect,” that is when the RX light strobes, even without any wires in the Arduino.

Thanks to all of you for a wonderful program and website! I hope you guys can help me as this has really set back my home cockpit.

Feb 20 in Wiring, Powering by

1 Answer

The Rx  always blink, that means the data exchange is normal, because the plugin constantly send various "service"  data to the board when connection is established.

If you have quite long wires (read information here about wiring), and you have some "data flickering" effect, make sure that you have soldered the pull-up resistor to the MUX boards as described here (see [Signal "flickering" issues]).

Or, (if I understand not correctly above) if you have not worked switches at all, check your wiring (address lines) and power or try to replace multiplexer.

P.S. of course you never have to buy new boards, reinstall planes, X-Plane, etc.
The "problem" is usually simpler.

PPS -  maybe you accidentally connected input Mux to the assigned output  ( as you have assigned and not used output Mux  on pin #13)?



Feb 20 by
Thanks for the quick response. I never used a resistor before. I checked everything else you said so it must be the resistors.
Last thing here Vlad. I tried to connect up with a single multiplexer held in the palm of my hand. The wire was less than a couple inches yet still no sign or response. I have the multiplexer assigned to pin 4 so it’s not an output... Any other suggestions?
It's simple system, nothing special,  I can't say more, just check (and read) everything again....