qmk_firmware

QMK firmware for my keyboards (Corne, Sweep Ferris) and trackball (Ploopy Adept)
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sn74x138.h (1394B)

      1 /* Copyright 2022
      2  *
      3  * This program is free software: you can redistribute it and/or modify
      4  * it under the terms of the GNU General Public License as published by
      5  * the Free Software Foundation, either version 2 of the License, or
      6  * (at your option) any later version.
      7  *
      8  * This program is distributed in the hope that it will be useful,
      9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
     10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     11  * GNU General Public License for more details.
     12  *
     13  * You should have received a copy of the GNU General Public License
     14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
     15  */
     16 
     17 #pragma once
     18 
     19 #include <stdint.h>
     20 #include <stdbool.h>
     21 
     22 /**
     23  * Driver for 74x138 3-to-8 decoder/demultiplexer with inverting outputs
     24  * https://assets.nexperia.com/documents/data-sheet/74HC_HCT138.pdf
     25  */
     26 
     27 /**
     28  * Initialize the address and output enable pins.
     29  */
     30 void sn74x138_init(void);
     31 
     32 /**
     33  * Set the enabled state.
     34  *
     35  * When enabled is true, pulls the E1 and E2 pins low, and the E3 pin high.
     36  *
     37  * \param enabled The enable state to set.
     38  */
     39 void sn74x138_set_enabled(bool enabled);
     40 
     41 /**
     42  * Set the output pin address.
     43  *
     44  * The selected output pin will be pulled low, while the remaining output pins will be high.
     45  *
     46  * \param address The address to set, from 0 to 7.
     47  */
     48 void sn74x138_set_addr(uint8_t address);