src/main/drivers/io_types.h

   1 /*
   2  * This file is part of Cleanflight and Betaflight.
   3  *
   4  * Cleanflight and Betaflight are free software. You can redistribute
   5  * this software and/or modify this software under the terms of the
   6  * GNU General Public License as published by the Free Software
   7  * Foundation, either version 3 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * Cleanflight and Betaflight are distributed in the hope that they
  11  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  12  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software.
  17  *
  18  * If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #pragma once
  22
  23 #include <stdint.h>
  24
  25 // IO pin identification
  26 // make sure that ioTag_t can't be assigned into IO_t without warning
  27 typedef uint8_t ioTag_t;       // packet tag to specify IO pin
  28 typedef void* IO_t;            // type specifying IO pin. Currently ioRec_t pointer, but this may change
  29
  30 // NONE initializer for ioTag_t variables
  31 #define IO_TAG_NONE 0
  32
  33 // NONE initializer for IO_t variable
  34 #define IO_NONE ((IO_t)0)
  35
  36 // both ioTag_t and IO_t are guarantied to be zero if pinid is NONE (no pin)
  37 // this simplifies initialization (globals are zeroed on start) and allows
  38 //  omitting unused fields in structure initializers.
  39 // it is also possible to use IO_t and ioTag_t as boolean value
  40 //   TODO - this may conflict with requirement to generate warning/error on IO_t - ioTag_t assignment
  41 //   IO_t being pointer is only possibility I know of ..
  42
  43 // pin config handling
  44 // pin config is packed into ioConfig_t to decrease memory requirements
  45 // IOCFG_x macros are defined for common combinations for all CPUs; this
  46 //  helps masking CPU differences
  47
  48 typedef uint8_t ioConfig_t;  // packed IO configuration