Wawa:
I seems you want to control some valves ? (type, voltage, current) ?
With a microcontroller with limited outputs ? (is it already used for other things) ?
You have already decided you need relays for that ?Why do you think a multiplexer is the answer.
Time division muxing is ok for LEDs (persistence of vision), but not for relays.
A shift register could be a better solution (depending on the rest of the hardware).
Post links to the valves.
Leo..
Yes. limit output.
I am just saying that multiplexer is one of the solution that I am considering. It should be demultiplexer according to PaulRB which I made a mistake here.
If I am not wrong, shift register is shift the output state across the output pin which I don't think suitable for my case because I need to switch on the relay individually. Correct me if I am wrong.
PaulRB:
I think the OP meant to say demultiplexer.Yes, is possible with an Uno. No, I don't think a switch case would be suitable.
I would suggest holding the 16 output pin numbers in an array. Also hold the 4 input pin numbers in a second array. Read the 4 input pins and turn those readings into a number between 0 and 15 using bitWrite(). This number can then be used to look up the output pin number from the array.
I see. Alright, thank you very much for your advice.
If i using the bitWrite function, the output will hold until i set it to OFF?
or i need delay and interrupt timer functiona also?
Grumpy_Mike:
Who said anything about designing a PCB?Without real information we can only offer you so much advice. Stupid artificial constraints don't go down well here.
You don't have any post where you live?
Because my boss dont want to spend much time on PCB design problems, like deal will supplier, trial and error.
Sorry that i cant provide much detail because now is still in design concept stage. If we know that Arduino isn't a good choice then we might change to other solution. That is why I am asking in this forum here because I don't know much about Arduino.
Basically we just need a device that can control multiple output individually with latch function, it must be low cost and finished products, like Arduino which we can buy and use it immediately.
Nope, just that i cant found any 8 bit latched module in the market of my country.