BBB UART4 and PPS overlay

I’ve been trying to build a GPS NTP server using BeagleBone Black Rev C and the AdaFruit Ultimate GPS breakout board. I started out using the as-shipped BBB Linux image and followed some similar online examples. The breakout board provides the Tx/Rx pins for NMEA data and a PPS output for feeding into the BBB. I was using the built-in UART4 overlay and then used a custom overlay for feeding the PPS signal into BBB 9.12 (GPIO_60). I had it basically working but then decided to load the latest BBB image and reconstruct the setup. The problem that I’m having is that the setup for overlays and whatnot seems completely different. There is no /sys/devices/platform/bone_capemgr/slots file so none of the instructions I previously used for setting up these overlays seems relevant. I don’t really have much experience (practically none) working with these overlays so I’m kind of lost at the moment. I had just started to get a basic understanding of the overlays and now I have no slots file to work with. Can anybody give me some guidance or point me to some references that might help me set this up on a recent Debian kernel?

uname -r

The image that I burned onto the BBB eMMC was Debian 9.1 2017-09-21 4GB IoT SD

All "overlay" etc control has moved to U-Boot:

Use the:


options in /boot/uEnv.txt to load your custom cape..