I believe for previous versions of B the GPIO pins booted up with 3.3 V then went to their software defined values after about 10 seconds. If I'm wrong about that just leave a comment to let me know what's right, but I was wondering if anything the boot values for those pins changed with the B+ revisions.
Thank you!
Re: GPIO values at boot
I'm not sure your understanding is correct. A way to check would be to connect a LED/resistor pair to each gpio and switch on. Watch for flickering.
Re: GPIO values at boot
What I eventually am going to try and do is put the pi in a chassis and control rf switches with it remotely. If the GPIO pins come up either hi, low, or high impedance disconnected, then it could determine how the interface circuit to the switches is configured.
So my best option is to troubleshoot it? I don't have to board yet. If the LED flickers, will that just tell me the loads not met/the voltage is too low to fully power the LED? Or would a DMM with ground to the GPIO pins be okay to get the actual value?
I'm new to Raspberry Pies and tinkering with it so I appreciate the help.
So my best option is to troubleshoot it? I don't have to board yet. If the LED flickers, will that just tell me the loads not met/the voltage is too low to fully power the LED? Or would a DMM with ground to the GPIO pins be okay to get the actual value?
I'm new to Raspberry Pies and tinkering with it so I appreciate the help.
Re: GPIO values at boot
Have a look at http://www.raspberrypi.org/documentatio ... uration.md and http://www.raspberrypi.org/documentatio ... /README.md and the "Pull" column of http://elinux.org/RPi_BCM2835_GPIOs
The Pi's pins are all digital, so are either 0V or 3.3V, there's no in-between values (ignoring PWM for now).the voltage is too low to fully power the LED?