mbed library sources modified for open wear
Dependents: openwear-lifelogger-example
Fork of mbed-src by
Diff: targets/hal/TARGET_NXP/TARGET_LPC176X/analogout_api.c
- Revision:
- 13:0645d8841f51
- Parent:
- 10:3bc89ef62ce7
- Child:
- 19:398f4c622e1b
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_NXP/TARGET_LPC176X/analogout_api.c Mon Aug 05 14:12:34 2013 +0300 @@ -0,0 +1,78 @@ +/* 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 "analogout_api.h" + +#include "cmsis.h" +#include "pinmap.h" +#include "error.h" + +static const PinMap PinMap_DAC[] = { + {P0_26, DAC_0, 2}, + {NC , NC , 0} +}; + +void analogout_init(dac_t *obj, PinName pin) { + obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC); + if (obj->dac == (uint32_t)NC) { + error("DAC pin mapping failed"); + } + + // power is on by default, set DAC clk divider is /4 + LPC_SC->PCLKSEL0 &= ~(0x3 << 22); + + // map out (must be done before accessing registers) + pinmap_pinout(pin, PinMap_DAC); + + analogout_write_u16(obj, 0); +} + +void analogout_free(dac_t *obj) {} + +static inline void dac_write(int value) { + value &= 0x3FF; // 10-bit + + // Set the DAC output + LPC_DAC->DACR = (0 << 16) // bias = 0 + | (value << 6); +} + +static inline int dac_read() { + return (LPC_DAC->DACR >> 6) & 0x3FF; +} + +void analogout_write(dac_t *obj, float value) { + if (value < 0.0f) { + dac_write(0); + } else if (value > 1.0f) { + dac_write(0x3FF); + } else { + dac_write(value * (float)0x3FF); + } +} + +void analogout_write_u16(dac_t *obj, uint16_t value) { + dac_write(value >> 6); // 10-bit +} + +float analogout_read(dac_t *obj) { + uint32_t value = dac_read(); + return (float)value * (1.0f / (float)0x3FF); +} + +uint16_t analogout_read_u16(dac_t *obj) { + uint32_t value = dac_read(); // 10-bit + return (value << 6) | ((value >> 4) & 0x003F); +}