problems with shield pins

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Posts: 9
Joined: 26 Jan 2021 00:20

problems with shield pins

Post by tjansteman »

I bought a z-uno shield and encountered a problem with some pins when used as switches. When I use the z-uno in a breadboard the switches work fine but when I put in the shield pin 11 and 12 are always on. Any suggestions about what the fault is ? , i've used the example for four relays on the z-uno page.
Posts: 194
Joined: 04 Aug 2016 07:14

Re: problems with shield pins

Post by p0lyg0n1 »

1) Pin11 is used as OneWire bus pin on the shield. It has pull-up resistor. Seems that's why the relay is always on.
2) Pin12 doesn't have "hardware" pull-up. I don't know why it has logic 1 level in your case.
Which type of relay do you use? Is it a module or original electromechanical relay without any additional components? Shield is able to control high current load only by means of PWM1-PWM4 terminals. Shield is able to control modules with 3v logic on another terminals(module has to meet current requirements of Z-Uno in this case: current on the one pin < 5mA), but you have to set the jumpers right way. Don't use pin11 because of integrated pull-up.
Please use the configurator tool to achieve needed settings of the the SHIELD:

Best regards,
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