mbed-os/targets/TARGET_Freescale/TARGET_K20XX/analogout_api.c

90 lines
2.4 KiB
C

/* mbed Microcontroller Library
* Copyright (c) 2006-2015 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"
#if DEVICE_ANALOGOUT
#include "cmsis.h"
#include "pinmap.h"
#include "PeripheralPins.h"
#define RANGE_12BIT 0xFFF
void analogout_init(dac_t *obj, PinName pin) {
obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
MBED_ASSERT(obj->dac != (DACName)NC);
SIM->SCGC2 |= SIM_SCGC2_DAC0_MASK;
uint32_t port = (uint32_t)pin >> PORT_SHIFT;
SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port);
DAC0->DAT[obj->dac].DATH = 0;
DAC0->DAT[obj->dac].DATL = 0;
DAC0->C1 = DAC_C1_DACBFMD_MASK; // One-Time Scan Mode
DAC0->C0 = DAC_C0_DACEN_MASK // Enable
| DAC_C0_DACSWTRG_MASK // Software Trigger
| DAC_C0_DACRFS_MASK; // VDDA selected
analogout_write_u16(obj, 0);
}
void analogout_free(dac_t *obj) {}
static inline void dac_write(dac_t *obj, int value) {
DAC0->DAT[obj->dac].DATL = (uint8_t)( value & 0xFF);
DAC0->DAT[obj->dac].DATH = (uint8_t)((value >> 8) & 0xFF);
}
static inline int dac_read(dac_t *obj) {
return ((DAC0->DAT[obj->dac].DATH << 8) | DAC0->DAT[obj->dac].DATL);
}
void analogout_write(dac_t *obj, float value) {
if (value < 0.0) {
dac_write(obj, 0);
} else if (value > 1.0) {
dac_write(obj, RANGE_12BIT);
} else {
dac_write(obj, value * (float)RANGE_12BIT);
}
}
void analogout_write_u16(dac_t *obj, uint16_t value) {
dac_write(obj, value >> 4); // 12-bit
}
float analogout_read(dac_t *obj) {
uint32_t value = dac_read(obj);
return (float)value * (1.0f / (float)RANGE_12BIT);
}
uint16_t analogout_read_u16(dac_t *obj) {
uint32_t value = dac_read(obj); // 12-bit
return (value << 4) | ((value >> 8) & 0x003F);
}
const PinMap *analogout_pinmap()
{
return PinMap_DAC;
}
#endif