/* mbed Microcontroller Library * Copyright (c) 2006-2013 ARM Limited * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "mbed_assert.h" #include "analogout_api.h" #include "cmsis.h" #include "pinmap.h" void analogout_init(dac_t *obj, PinName pin) { MBED_ASSERT(pin == P0_12); LPC_SYSCON->SYSAHBCLKCTRL0 |= (1 << 29); LPC_SYSCON->PDRUNCFG &= ~(1 << 12); LPC_IOCON->PIO0_12 = 0; LPC_SWM->PINENABLE0 &= ~(1 << 24); LPC_DAC->CTRL = 0; analogout_write_u16(obj, 0); } void analogout_free(dac_t *obj) { LPC_SYSCON->SYSAHBCLKCTRL0 &= ~(1 << 29); LPC_SWM->PINENABLE0 |= (1 << 24); } static inline void dac_write(int value) { value &= 0xFFF; // 12-bit // Set the DAC output LPC_DAC->VAL = (value << 4); } static inline int dac_read() { return ((LPC_DAC->VAL >> 4) & 0xFFF); } void analogout_write(dac_t *obj, float value) { if (value < 0.0f) { dac_write(0); } else if (value > 1.0f) { dac_write(0xFFF); } else { dac_write((uint32_t)(value * (float)0xFFF)); } } void analogout_write_u16(dac_t *obj, uint16_t value) { dac_write(value); } float analogout_read(dac_t *obj) { uint32_t value = dac_read(); return (float)value * (1.0f / (float)0xFFF); } uint16_t analogout_read_u16(dac_t *obj) { return (uint16_t)dac_read(); }