john thorne
New Member
Can I connect the outputs from 3 picaxe 18m2 to one ULN2803 input.
Effectively giving me an or gate.
Thanks
Effectively giving me an or gate.
Thanks
Thanks for the quick reply. That will work for me.Welcome to the PICAXE Forum
You cannot connect outputs directly ( or rather shouldn't ), but you can put a diode in each output line to create a diode-OR gate. Anodes to PICAXE, cathodes joined, to ULN.
An example of two different interpretations of the OPs original text - "outputs from 3 picaxe 18m2".Finally, there is another alternative: do the "or" function in software and use a spare PICAXE output to drive a single darlington.
This is the way we would also recommend. Remember to link all 0V rails together.Connect 3 PICAXE outputs to 3 inputs on the ULN2803. Then common the 3 associated darlington collectors together. The load, of course, will go between the +ve rail and the collectors. Turning on any darlington will energise the load.