Got it working without the GPIO expander,

I used GPIO19 for the status pin, which really needs a 'regular' GPIO, not an I2C pin.

Then I used a gpio= statement in config.txt to set GPIO3 (which is an I2C pin) to low on bootup. GPIO3's then used as the shutdown pin for the PowerBlock.

This arrangement works fine.

@petrockblog -- perhaps the documentation could be updated to make clear that GPIOs with hardwired pullup resistors (such as the I2C pins) cannot be used as the status pin?

Thanks,
Chris

@bpugh Ah, yes. I misread your previous post and had the 5V IN pins in mind. I bet higher gauge wires from 5V OUT to the Raspberry 5V IN and GND will do the trick.

I think I screwed something up on the pre-made retroie image. Because I re-flashed the pi and set I2C to be loaded through sudo raspi-config, now when I reboot it does detect my I2C. One step closer to my mobile retropie!

@krullbeast said in can udev read i2c and hardwired GPIO buttons simultaneously?:

do you think it is possible to read the i2c data and also the A and B buttons inside of retroarch?

Not an expert on this, but I think RetroArch doesn't read directly from GPIO (I2C or otherwise), instead it uses an established input driver (udev/sdl/etc.) - https://github.com/libretro/RetroArch/tree/master/input/drivers.

Revision 1.1 of the PowerBlock (introduced last year) provides break out pins for all needed signals. There is a brief blog post about it at https://blog.petrockblock.com/2016/05/20/new-revision-of-the-powerblock-increased-flexibility/. Maybe that gives some more insights.

@ByteThis Fruitbox sounds cool m8! I’ll have a look into that. I’m running Hyperpie … it’s not the smoothest but an overclock helped with that a bit 👍 Found Fruitbox: https://forums.raspberrypi.com/viewtopic.php?t=188723

Awesome build. Always was a fan of the fat ps2. Mine still works!

Well this is what happens when you realize Retropie doesn't yet support direct I2C connections.

Re-attached half of a nunchuck cable, going the Bluetooth route as it seems that's the only way to connect a Wii controller+accessory to Retropie.

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