1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
|
/* 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 "adc_iodefine.h"
#include "cpg_iodefine.h"
#define ANALOGIN_MEDIAN_FILTER 0
static const PinMap PinMap_ADC[] = {
{P1_8, AN0, 1},
{P1_9, AN1, 1},
{P1_10, AN2, 1},
{P1_11, AN3, 1},
{P1_12, AN3, 1},
{P1_13, AN5, 1},
{P1_14, AN5, 1},
{P1_15, AN7, 1},
{NC, NC, 0}
};
static volatile uint16_t *ADCDR[] = {
&ADCADDRA,
&ADCADDRB,
&ADCADDRC,
&ADCADDRD,
&ADCADDRE,
&ADCADDRF,
&ADCADDRG,
&ADCADDRH,
};
void analogin_init(analogin_t *obj, PinName pin) {
obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
MBED_ASSERT(obj->adc != (ADCName)NC);
CPGSTBCR3 &= ~(1 << 1);
CPGSTBCR6 &= ~(1 << 7);
// 15: ADF 14: ADIE 13: ADST, [12:9] TRGS..0
// [8:6] CKS 010 :: 340tclk
// [5:3] MDS 000 :: single mode
// [2:0] CH 000 :: AN0
ADCADCSR = 0x0080;
pinmap_pinout(pin, PinMap_ADC);
}
static inline uint32_t adc_read(analogin_t *obj) {
volatile uint16_t data;
// Select the appropriate channel and start conversion
ADCADCSR &= 0xfff8;
ADCADCSR |= (1 << 13 | (obj->adc & 0x7));
// Wait end of conversion
do {
data = ADCADCSR;
} while (((data & (1 << 15)) == 0) || ((data & (1 << 13)) != 0));
// clear flag
ADCADCSR &= ~(1 << 15);
return ((*(ADCDR[obj->adc])) >> 4) & 0x0FFF; // 12 bits range
}
#if ANALOGIN_MEDIAN_FILTER
static inline void order(uint32_t *a, uint32_t *b) {
if (*a > *b) {
uint32_t t = *a;
*a = *b;
*b = t;
}
}
#endif
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 to 16-bit conversion
}
float analogin_read(analogin_t *obj) {
uint32_t value = adc_read_u32(obj);
return (float)value * (1.0f / (float)0x0FFF); // 12 bits range
}
|
