Either browse through the files to know your devices correct bone_capemgr number or try this
cd /sys/devices/ ls cd capemgr.x (choose from the list and replace the number for x) On Tuesday, 1 October 2013 01:14:21 UTC+5:30, marcus silva wrote: > > any one know how to acess pwm slots in > /sys/devices/bone_capemgr.9? > I try to just change from 8 to 9 and did not work. > I use bbb black with ubuntu precise and I cant find > /sys/devices/ocp.2/helper.14/AIN7 > or > /sys/devices/platform/tsc/ain1 > those ports are only availible by default in anstrong? > > > > 2013/9/2 T.Morgan <duna...@gmail.com <javascript:>> > >> I think most of us have got a single servo running on the BBB by now. Has >> anyone succeeded in using 3 or more PWM channels at the same time? >> >> I find that if I: >> >> $ echo am33xx_pwm > /sys/devices/bone_capemgr.8/slots >> $ echo bone_pwm_P8_13 > /sys/devices/bone_capemgr.8/slots >> $ echo bone_pwm_P8_19 > /sys/devices/bone_capemgr.8/slots >> $ echo bone_pwm_P9_14 > /sys/devices/bone_capemgr.8/slots >> $ echo bone_pwm_P9_16 > /sys/devices/bone_capemgr.8/slots >> >> Then directories /sys/devices/ocp.2/pwm_test_P8_13.xx and >> pwm_test_P9_14.xx contain the expected files and subdirectories: >> >> driver duty modalias period polarity power run subsystem uevent >> >> while directories /sys/devices/ocp.2/pwm_test_P8_19.xx and >> pwm_test_P9_16.xx only contain: >> >> modalias power subsystem uevent >> >> The uevent files for P8_13 and P9_14 both contain the line >> 'DRIVER=pwm_test' which is missing from the uevent files for P8_19 and >> P9_16. >> >> The output on pins P8_13 and P9_14 behaves as expected when I write to >> their period and duty files. >> >> Pins P8_19 and P9_16 are fixed high or low (depending on the history of >> tests run on them). >> >> If I reverse the order in which I load the PWM modules, P8_19 and P9_16 >> are good, P8_13 and P9_14 are bad. >> >> I notice that after loading the PWM module on, say, P8_13, the output on >> the second pin for that EHR, P8_19 immediately goes high. >> (This may be indicative of the driver messing up the 2nd channel while >> configuring the 1st.) >> >> Very occasionally, a second PWM channel can be opened on one of the EHRs. >> When this happens, writes to the channel's period file return error >> 'invalid argument'. >> >> I've observed the same behavior on Angstrom 6/20 and 8/21 (in desperation >> I downloaded a copy from the developer's site). >> I've tested this with the PWM pins unconnected, connected to LEDs through >> serial resistors, connected to a 7404 and connected to L293Ds. >> I've tested this with the Adafruit BBIO library (0.17), shell commands as >> above, and using a homebrew python SYSFS front-end. >> >> Is there a bug in the test_pwm driver or am I missing some step in >> initializing the PWM channels? >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to the Google Groups >> "BeagleBoard" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to beagleboard...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > > > -- > Marcus de Vasconcelos Diogo da Silva > > "Uma montanha até um cego consegue desviar,mas é nas pedras menores que > nós muitas vezes tropeçamos e caimos!" > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
