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Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088_DM/analogin_api.c')
-rw-r--r--tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088_DM/analogin_api.c119
1 files changed, 119 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088_DM/analogin_api.c b/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088_DM/analogin_api.c
new file mode 100644
index 0000000000..e893fb60ba
--- /dev/null
+++ b/tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_NXP/TARGET_LPC408X/TARGET_LPC4088_DM/analogin_api.c
@@ -0,0 +1,119 @@
+/* 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"
+#include "mbed_error.h"
+
+#define ANALOGIN_MEDIAN_FILTER 1
+
+#define ADC_10BIT_RANGE 0x3FF
+#define ADC_12BIT_RANGE 0xFFF
+
+static inline int div_round_up(int x, int y) {
+ return (x + (y - 1)) / y;
+}
+
+static const PinMap PinMap_ADC[] = {
+ {P0_25, ADC0_2, 0x01},
+ {P0_26, ADC0_3, 0x01},
+ {NC , NC , 0 }
+};
+
+#define ADC_RANGE ADC_12BIT_RANGE
+
+void analogin_init(analogin_t *obj, PinName pin) {
+ obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
+ MBED_ASSERT(obj->adc != (ADCName)NC);
+
+ // ensure power is turned on
+ LPC_SC->PCONP |= (1 << 12);
+
+ uint32_t PCLK = PeripheralClock;
+
+ // calculate minimum clock divider
+ // clkdiv = divider - 1
+ uint32_t MAX_ADC_CLK = 12400000;
+ uint32_t clkdiv = div_round_up(PCLK, MAX_ADC_CLK) - 1;
+
+ // Set the generic software-controlled ADC settings
+ LPC_ADC->CR = (0 << 0) // SEL: 0 = no channels selected
+ | (clkdiv << 8) // CLKDIV:
+ | (0 << 16) // BURST: 0 = software control
+ | (1 << 21) // PDN: 1 = operational
+ | (0 << 24) // START: 0 = no start
+ | (0 << 27); // EDGE: not applicable
+
+ // must enable analog mode (ADMODE = 0)
+ __IO uint32_t *reg = (__IO uint32_t*) (LPC_IOCON_BASE + 4 * pin);
+ *reg &= ~(1 << 7);
+
+ pinmap_pinout(pin, PinMap_ADC);
+}
+
+static inline uint32_t adc_read(analogin_t *obj) {
+ // Select the appropriate channel and start conversion
+ LPC_ADC->CR &= ~0xFF;
+ LPC_ADC->CR |= 1 << (int)obj->adc;
+ LPC_ADC->CR |= 1 << 24;
+
+ // Repeatedly get the sample data until DONE bit
+ unsigned int data;
+ do {
+ data = LPC_ADC->GDR;
+ } while ((data & ((unsigned int)1 << 31)) == 0);
+
+ // Stop conversion
+ LPC_ADC->CR &= ~(1 << 24);
+
+ return (data >> 4) & ADC_RANGE; // 12 bit
+}
+
+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);
+}