Hi, i have recently started using arduino uno board. While i am still exploring, i was able to run few example programs to verify the board was not destroyed while shipping. I am trying to run 2 motors using a standard motor driver. I have configured 4-7 pins as outputs which goes as input to the L293 IC. I am not able to see any output signal out of the driver. While troubleshooting i was checking if the output pins on arduino had correct output. I was able to verify the value that i set using portOutputRegister() function while reading from the register. Also i tried to check the voltage on the output pins that i set as HIGH. I assumed these pins should have a voltage > 3.5V There was no voltage that got registered on my multimeter, and just shows some deflection of 10mV. Same with the 5V pin on arduino. The arduino is powered and has pin 13 kept to blink. But am not able to understand why the output pins 4 and 6 don't show some voltage. Can anyone please help me understand this?
If you haven’t already tried this,I would unhook anything you have hooked up to the Arduino and then run the simple blink sketch in the examples. Change the pin output number one at a time for the pins you want to measure and check the voltage. If that doesn’t work, then the chip may be bad.
It sounds like you haven’t set the pins to output mode in the software.
Thanks RPCoyle. I was able to confirm all the pins work fine. I suspect an issue in my old circuit where the ground of arduino, battery and motor might have not been connected together.