I've run into some issues with the new Pi zero W. First I tried to run an image of raspbian from 11-1-17' but that did nothing. Well, it booted but couldn't set up a Wi-Fi network. So I've installed a new image 16-2-17' and then the Wi-Fi worked like I expected.
Later, I updated a Pi 2 and swapped that SD card into the Pi zero W, and everything was working fine.
Then I changed the GPIO ports in some python programming and I got all sorts of errors (and again no Wi-Fi).
brcmfmac: brcmf_sdio_txfail: sdio error, abort command and terminate frame
brcmfmac: brcmf_sdiod_regrw_helper: failed to read data F1@0x0a020, err: -84
brcmfmac: brcmf_sdio_isr: failed backplane access
My first guess is that the onboard Wi-Fi is connected with the TTY GPIO. As I'm using it to read from a dutch smart meter (DSMR4.x), looks like I've got a conflict with the Wi-Fi.
UPDATE:
hunch was correct in the system log:
btuart[431]: Set Controller UART speed to 3000000 bit/s
Device setup complete
Started Configure Bluetooth Modems connected by UART.
So now the question is, how to use the UART/TTY with Bluetooth/Wi-Fi on a PI zero w?
UPDATE2:
I tried to disable Bluetooth using the /boot/config.txt
adding dtoverlay=pi3-disable-bt
but with no success. Bluetooth still gets loaded.
config.txt
along those lines (e.g. to disable bluetooth). If you aren't clear on what I'm talking about: raspberrypi.stackexchange.com/q/45570/5538 Also check the latest image for similar device tree related notes (in the boot parition).