BeagleBone Black RFID Adaptor Cape
Contents
Description
The RFID adaptor cape is an interface between the Beaglebone Black (BBB) and Texas Instrument's TRF7970ATB, (Multi-Protocol Fully Integrated 13.56-MHz RFID and NFC Transceiver) It allows users to have fully functional RFID and NFC capabilities on the BBB. The adaptor board also features four additional LEDs and a push button.
The communication between the BBB and the TB is via SPI. Since SPI pins are not automatically enabled on BBB, a device tree overlay is used to configure the pins properly for SPI use.
Schematic
Sample Code
The following code is our RFID C application. It will constantly scan for RFID tags within the vicinity of the reader. Once a tag is detected, its UID will be stored in uid.txt file.
RFID Application
SPI Device Tree Overlay Setup
The following information is slightly modified from BeagleBone Black Enable SPIDEV
NOTE: You MUST disable the HDMI interface to use SPI1 to talk to the adaptor cape.
Create a file called BB-SPI1-01-00A0.dts [[
Compile the dtc:
dtc -O dtb -o BB-SPI1-01-00A0.dtbo -b 0 -@ BB-SPI1-01-00A0.dts
Then, copy the file into /lib/firmware/:
cp BB-SPI1-01-00A0.dtbo /lib/firmware/
Then enable the device tree overlay:
echo BB-SPI1-01 > /sys/devices/bone_capemgr.*/slots
Plug in your BBB to a host computer using the mini usb data cable.
Go to My Computer>BeagleBone Getting Started> and open uEnv.txt Copy and paste this command into the .txt file. Make sure to save your changes. (Ctrl+s)
optargs=quiet drm.debug=7 capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN capemgr.enable_partno=BB-SPI1-01
Save the changes, reboot Beaglebone Black.
Make sure it is enabled
You should now have two spidev-files in the folder /dev/
ls -al /dev/spidev1.0
If you don't see it, you can type the following to manually enable the device tree overlay.
echo BB-SPI1-01 > /sys/devices/bone_capemgr.*/slots