mirror of https://github.com/ARMmbed/mbed-os.git
76 lines
2.0 KiB
C
76 lines
2.0 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"
|
|
#include "cmsis.h"
|
|
#include "pinmap.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);
|
|
MBED_ASSERT(obj->dac != (DACName)NC);
|
|
|
|
// 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);
|
|
}
|