Hello Devs,
I’ve been trying to enable eQEP for a rotary encoder on my BeagleBone Black using the latest Debian image. However, I couldn’t locate the epwmss devices at the expected paths:
/sys/devices/platform/ocp/48302000.epwmss/48302180.eqep/position
/sys/devices/platform/ocp/48304000.epwmss/48304180.eqep/position
/sys/devices/platform/ocp/48300000.epwmss/48300180.eqep/position
When I manually configure the pins for qep, I encounter the following error:
config-pin p8.11 qep && config-pin p8.12 qep
ERROR: open() for /sys/devices/platform/ocp/ocp:P8_11_pinmux/state failed, No such file or directory
I’ve also enabled QEP in the overlays, but it still doesn’t work.
This setup was previously working on another BeagleBone Black running Debian (unfortunately, I don’t recall the exact version as it has been reflashed). I purchased this BBB in April 2024.
Could there have been changes in the latest kernel affecting eQEP, or is there something I might be missing?
Any guidance would be greatly appreciated!
Best
Correct, 5.10.x uses the new ‘counter’ driver that went mainline for eqep positions… If you want the old interface, feel free to downgrade to 4.19.x-ti:
I’m looking to end the “update_kernel.sh” script, in Debian 10.x/11.x i’m working meta packages for kernel branches for users to more easily stay on a LTS kernel:
sudo apt-get update
sudo apt-get install bbb.io-kernel-4.19-ti-am335x
Regards,
Hello Robert,
Thank you very much for the information.
Could you please share any documentation on how to use the counter to read eQEP positions.
Thank you
Best
Hello Robert,
I have tried this, but counters are not enabled.
I am using P8.11 and P8.12 and bone_eqep2b-00A0
Here is the output of beagle-version and dmesg | grep qep doesn’t show anything.
eeprom:[A335BNLTEIA02335SBI00474]
model:[TI_AM335x_BeagleBone_Black]
dogtag:[BeagleBoard.org Debian Bullseye IoT Image 2023-09-02]
bootloader:[eMMC-(default)]:[/dev/mmcblk1]:[U-Boot SPL 2022.04-ge0d31da5 (Aug 04 2023 - 18:48:26 +0000)]:[location: dd MBR]
UBOOT: Booted Device-Tree:[am335x-boneblack-uboot-univ.dts]
UBOOT: Loaded Overlay:[BB-BONE-eMMC1-01-00A0.kernel]
UBOOT: Loaded Overlay:[bone_eqep2b-00A0]
kernel:[5.10.168-ti-r71]
nodejs:[v12.22.12]
/boot/uEnv.txt Settings:
uboot_overlay_options:[enable_uboot_overlays=1]
uboot_overlay_options:[uboot_overlay_addr4=/lib/firmware/bone_eqep2b-00A0.dtbo]
uboot_overlay_options:[disable_uboot_overlay_video=1]
uboot_overlay_options:[disable_uboot_overlay_audio=1]
uboot_overlay_options:[disable_uboot_overlay_wireless=1]
uboot_overlay_options:[disable_uboot_overlay_adc=1]
uboot_overlay_options:[enable_uboot_cape_universal=1]
pkg check: to individually upgrade run: [sudo apt install --only-upgrade <pkg>]
pkg:[bb-cape-overlays]:[4.14.20210821.0-0~bullseye+20210821]
pkg:[bb-customizations]:[1.20230720.1-0~bullseye+20230720]
pkg:[bb-usb-gadgets]:[1.20230414.0-0~bullseye+20230414]
pkg:[bb-wl18xx-firmware]:[1.20230414.0-0~bullseye+20230414]
pkg:[kmod]:[28-1]
WARNING:pkg:[librobotcontrol]:[NOT_INSTALLED]
pkg:[firmware-ti-connectivity]:[20210315-3]
groups:[debian : debian adm kmem dialout cdrom floppy audio dip video plugdev users systemd-journal input render bluetooth netdev i2c gpio admin tisdk weston-launch cloud9ide]
cmdline:[console=ttyS0,115200n8 bone_capemgr.uboot_capemgr_enabled=1 root=/dev/mmcblk1p1 ro rootfstype=ext4 rootwait coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet cape_universal=enable]
dmesg | grep remote
[ 10.155607] remoteproc remoteproc0: wkup_m3 is available
[ 37.493725] remoteproc remoteproc0: powering up wkup_m3
[ 37.493762] remoteproc remoteproc0: Booting fw image am335x-pm-firmware.elf, size 217148
[ 37.494044] remoteproc remoteproc0: remote processor wkup_m3 is now up
[ 51.419570] remoteproc remoteproc1: 4a334000.pru is available
[ 51.432361] remoteproc remoteproc2: 4a338000.pru is available
dmesg | grep pru
[ 51.419570] remoteproc remoteproc1: 4a334000.pru is available
[ 51.432361] remoteproc remoteproc2: 4a338000.pru is available
dmesg | grep pinctrl-single
[ 9.639074] pinctrl-single 44e10800.pinmux: 142 pins, size 568
dmesg | grep gpio-of-helper
[ 9.640668] gpio-of-helper ocp:cape-universal: Failed to get gpio property of 'P8_03'
[ 9.640698] gpio-of-helper ocp:cape-universal: Failed to create gpio entry
[ 10.353808] gpio-of-helper ocp:cape-universal: Allocated GPIO id=0 name='P8_03'
[ 10.354051] gpio-of-helper ocp:cape-universal: Allocated GPIO id=1 name='P8_04'
[ 10.354254] gpio-of-helper ocp:cape-universal: Allocated GPIO id=2 name='P8_05'
[ 10.354430] gpio-of-helper ocp:cape-universal: Allocated GPIO id=3 name='P8_06'
[ 10.354992] gpio-of-helper ocp:cape-universal: Allocated GPIO id=4 name='P8_07'
[ 10.355203] gpio-of-helper ocp:cape-universal: Allocated GPIO id=5 name='P8_08'
[ 10.355398] gpio-of-helper ocp:cape-universal: Allocated GPIO id=6 name='P8_09'
[ 10.355587] gpio-of-helper ocp:cape-universal: Allocated GPIO id=7 name='P8_10'
[ 10.355781] gpio-of-helper ocp:cape-universal: Allocated GPIO id=8 name='P8_11'
[ 10.355968] gpio-of-helper ocp:cape-universal: Allocated GPIO id=9 name='P8_12'
[ 10.356219] gpio-of-helper ocp:cape-universal: Allocated GPIO id=10 name='P8_13'
[ 10.356400] gpio-of-helper ocp:cape-universal: Allocated GPIO id=11 name='P8_14'
[ 10.356575] gpio-of-helper ocp:cape-universal: Allocated GPIO id=12 name='P8_15'
[ 10.356736] gpio-of-helper ocp:cape-universal: Allocated GPIO id=13 name='P8_16'
[ 10.356909] gpio-of-helper ocp:cape-universal: Allocated GPIO id=14 name='P8_17'
[ 10.357071] gpio-of-helper ocp:cape-universal: Allocated GPIO id=15 name='P8_18'
[ 10.357254] gpio-of-helper ocp:cape-universal: Allocated GPIO id=16 name='P8_19'
[ 10.357459] gpio-of-helper ocp:cape-universal: Allocated GPIO id=17 name='P8_20'
[ 10.357622] gpio-of-helper ocp:cape-universal: Allocated GPIO id=18 name='P8_21'
[ 10.357794] gpio-of-helper ocp:cape-universal: Allocated GPIO id=19 name='P8_22'
[ 10.357952] gpio-of-helper ocp:cape-universal: Allocated GPIO id=20 name='P8_23'
[ 10.358124] gpio-of-helper ocp:cape-universal: Allocated GPIO id=21 name='P8_24'
[ 10.358293] gpio-of-helper ocp:cape-universal: Allocated GPIO id=22 name='P8_25'
[ 10.358451] gpio-of-helper ocp:cape-universal: Allocated GPIO id=23 name='P8_26'
[ 10.358633] gpio-of-helper ocp:cape-universal: Allocated GPIO id=24 name='P8_27'
[ 10.358800] gpio-of-helper ocp:cape-universal: Allocated GPIO id=25 name='P8_28'
[ 10.359077] gpio-of-helper ocp:cape-universal: Allocated GPIO id=26 name='P8_29'
[ 10.359268] gpio-of-helper ocp:cape-universal: Allocated GPIO id=27 name='P8_30'
[ 10.359434] gpio-of-helper ocp:cape-universal: Allocated GPIO id=28 name='P8_31'
[ 10.359608] gpio-of-helper ocp:cape-universal: Allocated GPIO id=29 name='P8_32'
[ 10.359777] gpio-of-helper ocp:cape-universal: Allocated GPIO id=30 name='P8_33'
[ 10.359940] gpio-of-helper ocp:cape-universal: Allocated GPIO id=31 name='P8_34'
[ 10.360133] gpio-of-helper ocp:cape-universal: Allocated GPIO id=32 name='P8_35'
[ 10.360305] gpio-of-helper ocp:cape-universal: Allocated GPIO id=33 name='P8_36'
[ 10.360481] gpio-of-helper ocp:cape-universal: Allocated GPIO id=34 name='P8_37'
[ 10.360662] gpio-of-helper ocp:cape-universal: Allocated GPIO id=35 name='P8_38'
[ 10.360824] gpio-of-helper ocp:cape-universal: Allocated GPIO id=36 name='P8_39'
[ 10.360993] gpio-of-helper ocp:cape-universal: Allocated GPIO id=37 name='P8_40'
[ 10.361159] gpio-of-helper ocp:cape-universal: Allocated GPIO id=38 name='P8_41'
[ 10.361326] gpio-of-helper ocp:cape-universal: Allocated GPIO id=39 name='P8_42'
[ 10.361506] gpio-of-helper ocp:cape-universal: Allocated GPIO id=40 name='P8_43'
[ 10.361670] gpio-of-helper ocp:cape-universal: Allocated GPIO id=41 name='P8_44'
[ 10.361839] gpio-of-helper ocp:cape-universal: Allocated GPIO id=42 name='P8_45'
[ 10.361995] gpio-of-helper ocp:cape-universal: Allocated GPIO id=43 name='P8_46'
[ 10.362181] gpio-of-helper ocp:cape-universal: Allocated GPIO id=44 name='P9_11'
[ 10.362357] gpio-of-helper ocp:cape-universal: Allocated GPIO id=45 name='P9_12'
[ 10.362518] gpio-of-helper ocp:cape-universal: Allocated GPIO id=46 name='P9_13'
[ 10.362689] gpio-of-helper ocp:cape-universal: Allocated GPIO id=47 name='P9_14'
[ 10.362850] gpio-of-helper ocp:cape-universal: Allocated GPIO id=48 name='P9_15'
[ 10.363152] gpio-of-helper ocp:cape-universal: Allocated GPIO id=49 name='P9_16'
[ 10.363329] gpio-of-helper ocp:cape-universal: Allocated GPIO id=50 name='P9_17'
[ 10.363487] gpio-of-helper ocp:cape-universal: Allocated GPIO id=51 name='P9_18'
[ 10.363658] gpio-of-helper ocp:cape-universal: Allocated GPIO id=52 name='P9_19'
[ 10.363842] gpio-of-helper ocp:cape-universal: Allocated GPIO id=53 name='P9_20'
[ 10.364003] gpio-of-helper ocp:cape-universal: Allocated GPIO id=54 name='P9_21'
[ 10.364173] gpio-of-helper ocp:cape-universal: Allocated GPIO id=55 name='P9_22'
[ 10.364359] gpio-of-helper ocp:cape-universal: Allocated GPIO id=56 name='P9_23'
[ 10.364544] gpio-of-helper ocp:cape-universal: Allocated GPIO id=57 name='P9_24'
[ 10.365012] gpio-of-helper ocp:cape-universal: Allocated GPIO id=58 name='P9_25'
[ 10.365218] gpio-of-helper ocp:cape-universal: Allocated GPIO id=59 name='P9_26'
[ 10.365397] gpio-of-helper ocp:cape-universal: Allocated GPIO id=60 name='P9_27'
[ 10.365561] gpio-of-helper ocp:cape-universal: Allocated GPIO id=61 name='P9_28'
[ 10.365752] gpio-of-helper ocp:cape-universal: Allocated GPIO id=62 name='P9_29'
[ 10.365922] gpio-of-helper ocp:cape-universal: Allocated GPIO id=63 name='P9_30'
[ 10.366087] gpio-of-helper ocp:cape-universal: Allocated GPIO id=64 name='P9_31'
[ 10.366270] gpio-of-helper ocp:cape-universal: Allocated GPIO id=65 name='P9_41'
[ 10.366432] gpio-of-helper ocp:cape-universal: Allocated GPIO id=66 name='P9_91'
[ 10.366605] gpio-of-helper ocp:cape-universal: Allocated GPIO id=67 name='P9_42'
[ 10.366779] gpio-of-helper ocp:cape-universal: Allocated GPIO id=68 name='P9_92'
[ 10.366791] gpio-of-helper ocp:cape-universal: ready
dmesg | grep wlcore
lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
END
And here is my uEnv.txt
#Docs: http://elinux.org/Beagleboard:U-boot_partitioning_layout_2.0
uname_r=5.10.168-ti-r71
#uuid=
#dtb=
###U-Boot Overlays###
###Documentation: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_Overlays
###Master Enable
enable_uboot_overlays=1
###
###Overide capes with eeprom
#uboot_overlay_addr0=<file0>.dtbo
#uboot_overlay_addr1=<file1>.dtbo
#uboot_overlay_addr2=<file2>.dtbo
#uboot_overlay_addr3=<file3>.dtbo
###
###Additional custom capes
uboot_overlay_addr4=/lib/firmware/bone_eqep2-00A0.dtbo
#uboot_overlay_addr5=<file5>.dtbo
#uboot_overlay_addr6=<file6>.dtbo
#uboot_overlay_addr7=<file7>.dtbo
###
###Custom Cape
#dtb_overlay=<file8>.dtbo
###
###Disable auto loading of virtual capes (emmc/video/wireless/adc)
#disable_uboot_overlay_emmc=1
disable_uboot_overlay_video=1
disable_uboot_overlay_audio=1
disable_uboot_overlay_wireless=1
disable_uboot_overlay_adc=1
###
###Cape Universal Enable
enable_uboot_cape_universal=1
###
###Debug: disable uboot autoload of Cape
#disable_uboot_overlay_addr0=1
#disable_uboot_overlay_addr1=1
#disable_uboot_overlay_addr2=1
#disable_uboot_overlay_addr3=1
###
###U-Boot fdt tweaks... (60000 = 384KB)
#uboot_fdt_buffer=0x60000
###U-Boot Overlays###
console=ttyS0,115200n8
cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet cape_universal=enable
#In the event of edid real failures, uncomment this next line:
#cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet video=HDMI-A-1:1024x768@60e
#Use an overlayfs on top of a read-only root filesystem:
#cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet overlayroot=tmpfs
##enable Generic eMMC Flasher:
#cmdline=init=/usr/sbin/init-beagle-flasher
I tried the same with bone_eqep2b-00A0 but no luck.
Note: In the documentation it is given that eqep2 wotks at p8.11 and 8.12 however, if we look at the .dts file of eqep2 it shows pine p8.41 and p8.42. epep2b is at p8.11 and p8.12 according to the dts file.
Thank you
Please guide
is the driver loaded?
debian@23-am335x-bbb:/sys/bus/counter$ uname -r
5.10.168-ti-r79
debian@23-am335x-bbb:/sys/bus/counter$ lsmod | grep counter
counter 24576 1 ti_eqep
debian@23-am335x-bbb:/sys/bus/counter$ tree ./
./
├── devices
│ ├── counter0 -> ../../../devices/platform/ocp/48000000.interconnect/48000000.interconnect:segment@300000/48300000.target-module/48300000.epwmss/48300180.counter/counter0
│ ├── counter1 -> ../../../devices/platform/ocp/48000000.interconnect/48000000.interconnect:segment@300000/48302000.target-module/48302000.epwmss/48302180.counter/counter1
│ └── counter2 -> ../../../devices/platform/ocp/48000000.interconnect/48000000.interconnect:segment@300000/48304000.target-module/48304000.epwmss/48304180.counter/counter2
├── drivers
├── drivers_autoprobe
├── drivers_probe
└── uevent
5 directories, 3 files
Hi Robert,
Yes the driver is loaded.
debian@beaglebone:/sys/bus/counter$ uname -r
5.10.168-ti-r71
debian@beaglebone:/sys/bus/counter$ lsmod | grep counter
counter 24576 1 ti_eqep
debian@beaglebone:/sys/bus/counter$ tree ./
./
|-- devices
| |-- counter0 -> ../../../devices/platform/ocp/48000000.interconnect/48000000.interconnect:segment@300000/48300000.target-module/48300000.epwmss/48300180.counter/counter0
| |-- counter1 -> ../../../devices/platform/ocp/48000000.interconnect/48000000.interconnect:segment@300000/48302000.target-module/48302000.epwmss/48302180.counter/counter1
| `-- counter2 -> ../../../devices/platform/ocp/48000000.interconnect/48000000.interconnect:segment@300000/48304000.target-module/48304000.epwmss/48304180.counter/counter2
|-- drivers
|-- drivers_autoprobe
|-- drivers_probe
`-- uevent
5 directories, 3 files
When I fallback to kernel 4.19 it works. However, it doesn’t work with latest kernel.
Is there a way I can make it work on the latest kernel?
Thank you
Best