hal_bb_gpio - Driver for beaglebone GPIO pins

bb_gpio.read
              Update HAL pins from physical pins.

       bb_gpio.write
              Update physical pins from HAL pins.

       The input_pins loadrt parameter controls which physical I/O pins are available to HAL as input pins.  The
       numbering  is  "800+N"  for  pin  N on connector P8, and "900+N" for pin N on connector P9.  For example,
       "803" means connector P8 pin 3, which is also described in BeagleBone documentation as "gpmc_ad6".

       Specifying pins that are otherwise in use by the system  may  have  undesirable  side  effects,  such  as
       crashing rtapi_app or the whole system.

   PINSbb_gpio.pN.in-NN bit out
       bb_gpio.pN.in-NN-invert bit in
              in-NN  is  a  snapshot  of  the  value  of  the  corresponding  physical  pin XOR the value of the
              corresponding in-NN-invert pin.

       GPL

LinuxCNC Documentation                                                                            hal_bb_gpio(9)

       hal_bb_gpio - Driver for beaglebone GPIO pins

       The input_pins loadrt parameter controls which physical I/O pins are available to HAL as input pins.  The
       numbering is "800+N" for pin N on connector P8, and "900+N" for pin N on connector P9.

       Specifying pins that are otherwise in use by the system  may  have  undesirable  side  effects,  such  as
       crashing rtapi_app or the whole system.

   PINSbb_gpio.pN.out-NN bit out
       bb_gpio.pN.out-NN-invert bit in
              The corresponding physical pin is driven with the result of in-NN xor in-NN-invert.

       None

loadrthal_bb_gpiouser_leds=#,...input_pins=#,...output_pins=#,...

       The  user_leds loadrt parameter controls which LEDs are available to HAL.  Valid range: 0..3.  These LEDs
       are next to the ethernet jack  and  the  LinuxCNC  numbers  match  the  silkscreen  on  beaglbone  black.
       Empirically, these seem to be OR'd with whatever function is assigned to the LED in Linux.

   PINSbb_gpio.userledN bit in
       bb_gpio.userledN-invert bit in
              The associated LED is lit if userledN xor userledN-invert isTRUE.