diff options
Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC15XX/analogin_api.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC15XX/analogin_api.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC15XX/analogin_api.c b/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC15XX/analogin_api.c new file mode 100644 index 0000000000..da3bcef999 --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC15XX/analogin_api.c @@ -0,0 +1,158 @@ +/* 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 "analogin_api.h" +#include "cmsis.h" +#include "pinmap.h" + +#define ANALOGIN_MEDIAN_FILTER 1 + +#define ADC_10BIT_RANGE 0x3FF +#define ADC_12BIT_RANGE 0xFFF + +#define ADC_RANGE ADC_12BIT_RANGE + +static const PinMap PinMap_ADC[] = { + {P0_8 , ADC0_0, 0}, + {P0_7 , ADC0_1, 0}, + {P0_6 , ADC0_2, 0}, + {P0_5 , ADC0_3, 0}, + {P0_4 , ADC0_4, 0}, + {P0_3 , ADC0_5, 0}, + {P0_2 , ADC0_6, 0}, + {P0_1 , ADC0_7, 0}, + {P1_0 , ADC0_8, 0}, + {P0_31, ADC0_9, 0}, + {P0_0 , ADC0_10,0}, + {P0_30, ADC0_11,0}, + {P1_1 , ADC1_0, 0}, + {P0_9 , ADC1_1, 0}, + {P0_10, ADC1_2, 0}, + {P0_11, ADC1_3, 0}, + {P1_2 , ADC1_4, 0}, + {P1_3 , ADC1_5, 0}, + {P0_13, ADC1_6, 0}, + {P0_14, ADC1_7, 0}, + {P0_15, ADC1_8, 0}, + {P0_16, ADC1_9, 0}, + {P1_4 , ADC1_10,0}, + {P1_5 , ADC1_11,0}, +}; + +void analogin_init(analogin_t *obj, PinName pin) { + obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC); + MBED_ASSERT(obj->adc != (ADCName)NC); + + uint32_t port = (pin >> 5); + // enable clock for GPIOx + LPC_SYSCON->SYSAHBCLKCTRL0 |= (1UL << (14 + port)); + // pin enable + LPC_SWM->PINENABLE0 &= ~(1UL << obj->adc); + // configure GPIO as input + LPC_GPIO_PORT->DIR[port] &= ~(1UL << (pin & 0x1F)); + + // power up ADC + if (obj->adc < ADC1_0) + { + // ADC0 + LPC_SYSCON->PDRUNCFG &= ~(1 << 10); + LPC_SYSCON->SYSAHBCLKCTRL0 |= (1 << 27); + } + else { + // ADC1 + LPC_SYSCON->PDRUNCFG &= ~(1 << 11); + LPC_SYSCON->SYSAHBCLKCTRL0 |= (1 << 28); + } + + // select IRC as asynchronous clock, divided by 1 + LPC_SYSCON->ADCASYNCCLKSEL = 0; + LPC_SYSCON->ADCASYNCCLKDIV = 1; + + __IO LPC_ADC0_Type *adc_reg = (obj->adc < ADC1_0) ? (__IO LPC_ADC0_Type*)(LPC_ADC0) : (__IO LPC_ADC0_Type*)(LPC_ADC1); + + // determine the system clock divider for a 500kHz ADC clock during calibration + uint32_t clkdiv = (SystemCoreClock / 500000) - 1; + + // perform a self-calibration + adc_reg->CTRL = (1UL << 30) | (clkdiv & 0xFF); + while ((adc_reg->CTRL & (1UL << 30)) != 0); + + // switch to asynchronous mode + adc_reg->CTRL = (1UL << 8); +} + +static inline uint32_t adc_read(analogin_t *obj) { + uint32_t channels; + + __IO LPC_ADC0_Type *adc_reg = (obj->adc < ADC1_0) ? (__IO LPC_ADC0_Type*)(LPC_ADC0) : (__IO LPC_ADC0_Type*)(LPC_ADC1); + + if (obj->adc >= ADC1_0) + channels = ((obj->adc - ADC1_0) & 0x1F); + else + channels = (obj->adc & 0x1F); + + // select channel + adc_reg->SEQA_CTRL &= ~(0xFFF); + adc_reg->SEQA_CTRL |= (1UL << channels); + + // start conversion and sequence enable + adc_reg->SEQA_CTRL |= ((1UL << 26) | (1UL << 31)); + + // Repeatedly get the sample data until DONE bit + volatile uint32_t data; + do { + data = adc_reg->SEQA_GDAT; + } while ((data & (1UL << 31)) == 0); + + // Stop conversion + adc_reg->SEQA_CTRL &= ~(1UL << 31); + + return ((data >> 4) & ADC_RANGE); +} + +static inline void order(uint32_t *a, uint32_t *b) { + if (*a > *b) { + uint32_t t = *a; + *a = *b; + *b = t; + } +} + +static inline uint32_t adc_read_u32(analogin_t *obj) { + uint32_t value; +#if ANALOGIN_MEDIAN_FILTER + uint32_t v1 = adc_read(obj); + uint32_t v2 = adc_read(obj); + uint32_t v3 = adc_read(obj); + order(&v1, &v2); + order(&v2, &v3); + order(&v1, &v2); + value = v2; +#else + value = adc_read(obj); +#endif + return value; +} + +uint16_t analogin_read_u16(analogin_t *obj) { + uint32_t value = adc_read_u32(obj); + return (value << 4) | ((value >> 8) & 0x000F); // 12 bit +} + +float analogin_read(analogin_t *obj) { + uint32_t value = adc_read_u32(obj); + return (float)value * (1.0f / (float)ADC_RANGE); +} |