/* Abstract bitwise GPIO services */ // Copyright (C)2013-2018, Philip Munts, President, Munts AM Corp. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are met: // // * Redistributions of source code must retain the above copyright notice, // this list of conditions and the following disclaimer. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE // POSSIBILITY OF SUCH DAMAGE. #include #define MAX_GPIO_PORTS 5 #define PINS_PER_GPIO_PORT 32 static LPC_GPIO_TypeDef * const PORTS[] = { LPC_GPIO0, LPC_GPIO1, LPC_GPIO2, LPC_GPIO3, LPC_GPIO4 }; int gpio_configure(unsigned pin, unsigned direction) { unsigned int port; // Split into port and pin components port = pin / PINS_PER_GPIO_PORT; pin = pin % PINS_PER_GPIO_PORT; // Validate parameters if (port >= MAX_GPIO_PORTS) { errno_r = EINVAL; return -1; } if (direction > GPIO_DIR_OUTPUT) { errno_r = EINVAL; return -1; } // Configure the pin PORTS[port]->FIOMASK &= ~(1 << pin); PORTS[port]->FIODIR |= (direction << pin); return 0; } int gpio_read(unsigned pin) { unsigned int port; // Split into port and pin components port = pin / PINS_PER_GPIO_PORT; pin = pin % PINS_PER_GPIO_PORT; // Validate parameters if (port >= MAX_GPIO_PORTS) { errno_r = EINVAL; return -1; } // Read the pin state return (PORTS[port]->FIOPIN >> pin) & 0x01; } int gpio_write(unsigned pin, bool state) { unsigned int port; // Split into port and pin components port = pin / PINS_PER_GPIO_PORT; pin = pin % PINS_PER_GPIO_PORT; // Validate parameters if (port >= MAX_GPIO_PORTS) { errno_r = EINVAL; return -1; } // Write the pin state if (state) PORTS[port]->FIOSET = 1 << pin; else PORTS[port]->FIOCLR = 1 << pin; return 0; }