2017 Jun 10, 01:11 AM
I think I found a solution to the power up problem.
All you need to do is add a 10k pull up resistor from pin_sr_noe (pin 11 on the Pi) to the 5v line.
Actually on the shift register diagram it would be between the purple input wire from the Pi to the 5V rail.
I tried it here and it is working using a SainSmart relay board.
I still need to do some further testing. It may be possible to enable a pull up on the Pi through software. I'll post back after I test. Short on time riight now
Dan
All you need to do is add a 10k pull up resistor from pin_sr_noe (pin 11 on the Pi) to the 5v line.
Actually on the shift register diagram it would be between the purple input wire from the Pi to the 5V rail.
I tried it here and it is working using a SainSmart relay board.
I still need to do some further testing. It may be possible to enable a pull up on the Pi through software. I'll post back after I test. Short on time riight now
Dan