/* Copyright 2022 * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include "sn74x138.h" #include "gpio.h" #define ADDRESS_PIN_COUNT 3 #ifndef SN74X138_ADDRESS_PINS # error sn74x138: no address pins defined! #endif static const pin_t address_pins[ADDRESS_PIN_COUNT] = SN74X138_ADDRESS_PINS; void sn74x138_init(void) { for (int i = 0; i < ADDRESS_PIN_COUNT; i++) { setPinOutput(address_pins[i]); writePinLow(address_pins[i]); } #if defined(SN74X138_E1_PIN) setPinOutput(SN74X138_E1_PIN); writePinHigh(SN74X138_E1_PIN); #endif #if defined(SN74X138_E2_PIN) setPinOutput(SN74X138_E2_PIN); writePinHigh(SN74X138_E2_PIN); #endif #if defined(SN74X138_E3_PIN) setPinOutput(SN74X138_E3_PIN); writePinLow(SN74X138_E3_PIN); #endif } void sn74x138_set_enabled(bool enabled) { #if defined(SN74X138_E1_PIN) writePin(SN74X138_E1_PIN, !enabled); #endif #if defined(SN74X138_E2_PIN) writePin(SN74X138_E2_PIN, !enabled); #endif #if defined(SN74X138_E3_PIN) writePin(SN74X138_E3_PIN, enabled); #endif } void sn74x138_set_addr(uint8_t address) { for (int i = 0; i < ADDRESS_PIN_COUNT; i++) { writePin(address_pins[i], address & (1 << i)); } }