summaryrefslogtreecommitdiff
path: root/tests/adc-power/adc-power.c
blob: 9b6df0783766b44d422d07e975312052afaef074 (plain)
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
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
/**
 * Testing ADC power up and power down, for timing and actual on/off
 * Uses TIM6, because DWT_CYCCNT not available on cm0(+) :(
 * (And with no DWT, no ITM timestamping either, get a real mcu!)
 */

#include <stdio.h>
#include <stdint.h>
#include <libopencm3/stm32/adc.h>
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/timer.h>

#include "adc-power.h"

/* Everyone has tim6 right? */
#define TIMER TIM6
#define TIMER_RCC RCC_TIM6

// TODO - stick this in libopencm3?
#define	ARRAY_SIZE(a)	(sizeof((a)) / sizeof((a)[0]))

// Still have some bad shit to deal with...
#if defined(STM32F0)
#define SEPARATE_ADC_SAMPLING 0
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_239DOT5 // 4usec or more for tempsensor
#elif defined(STM32F3)
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_181DOT5CYC
#define SAMPLE_TIME_TEMP ADC_SMPR_SMP_601DOT5CYC // 2.2usecs or more
#define SAMPLE_TIME_VREF SAMPLE_TIME_TEMP
#elif defined(STM32F4)
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_28CYC
#define SAMPLE_TIME_TEMP ADC_SMPR_SMP_144CYC // 10 usecs or more, in theory needs 840cycles!
#define SAMPLE_TIME_VREF SAMPLE_TIME_TEMP
#define ADC_CHANNEL_TEMP ADC_CHANNEL_TEMP_F40
#define SEPARATE_VREF 0
#elif defined(STM32L1)
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_24CYC
#define SAMPLE_TIME_TEMP ADC_SMPR_SMP_192CYC
#define SAMPLE_TIME_VREF SAMPLE_TIME_TEMP
#define SEPARATE_VREF 0
#elif defined(STM32L4)
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_247DOT5CYC
#define SAMPLE_TIME_TEMP ADC_SMPR_SMP_247DOT5CYC
#define SAMPLE_TIME_VREF SAMPLE_TIME_TEMP
#else
#error "no sample time for your target yet?!"
#endif

#ifndef SEPARATE_VREF
#define SEPARATE_VREF 1
#endif
#ifndef SEPARATE_ADC_SAMPLING
#define SEPARATE_ADC_SAMPLING 1
#endif


void adc_power_init(void)
{
	/* Some basic ADC config, that we won't touch again */
#if defined(STM32F3)
	/* silly f303 */
	rcc_periph_clock_enable(RCC_ADC12);
	rcc_adc_prescale(RCC_CFGR2_ADCxPRES_PLL_CLK_DIV_1, RCC_CFGR2_ADCxPRES_PLL_CLK_DIV_1);
	adc_enable_regulator(ADC1);
#elif defined (STM32L4)
	/* same same but different */
	rcc_periph_clock_enable(RCC_ADC1);
	ADC_CR(ADC1) &= ~ADC_CR_DEEPPWD;
	RCC_CCIPR |= 3 << 28; // system clock as adc clock.  (with CKMODE == 0)
	adc_enable_regulator(ADC1);
	
	ADC_CR(ADC1) &= ~ADC_CR_ADCALDIF;
	ADC_CR(ADC1) |= ADC_CR_ADCAL;
	while (ADC_CR(ADC1) & ADC_CR_ADCAL);
	

#else
	rcc_periph_clock_enable(RCC_ADC1);
#if 0
	// DANGER DANGER! doing this without DMA is dum.
	// but... we're busy polling, we should be right... right?
	// (dma across platforms is teh suck)
	adc_enable_scan_mode(ADC1);
	ADC_CR2 |= ADC_CR2_EOCS; // FIXME
#else
	// FIXME - f0!  adc_disable_scan_mode(ADC1);
#endif
	
#endif
#if (SEPARATE_ADC_SAMPLING == 1)
	adc_set_sample_time_on_all_channels(ADC1, SAMPLE_TIME_BASIC);
	adc_set_sample_time(ADC1, ADC_CHANNEL_TEMP, SAMPLE_TIME_TEMP);
	adc_set_sample_time(ADC1, ADC_CHANNEL_TEMP, SAMPLE_TIME_VREF);
#else
	adc_set_sample_time_on_all_channels(ADC1, SAMPLE_TIME_BASIC);
#endif
	adc_enable_temperature_sensor();
#if (SEPARATE_VREF == 1)
	adc_enable_vrefint();
#endif

	/*
	 * We're going to setup a timer to run at top speed, so... "fast" 
	 * but we don't actually care about the rate itself.  We just 
	 * want to collect how many ticks it takes to enable and disable
	 * the adc.
	 */
	rcc_periph_clock_enable(TIMER_RCC);
	timer_reset(TIMER);
	timer_set_prescaler(TIMER, 0);
	timer_enable_counter(TIMER);
}

static uint16_t read_adc_naiive(uint8_t channel)
{
	uint8_t channel_array[16];
	channel_array[0] = channel;
	adc_set_regular_sequence(ADC1, 1, channel_array);
	adc_start_conversion_regular(ADC1);
	while (!adc_eoc(ADC1));
	return adc_read_regular(ADC1);
}

static float adc_calc_tempf(unsigned int ts_v, unsigned int vref) {
	float adjusted_vtemp = ts_v * ST_VREFINT_CAL * 1.0f / vref * 1.0f;
	float slope = (110-30) * 1.0f / (ST_TSENSE_CAL2_110C - ST_TSENSE_CAL1_30C) * 1.0f;
	return slope * (adjusted_vtemp - ST_TSENSE_CAL1_30C) + 30;
}

static int adc_calc_tempi(unsigned int ts, unsigned int vref) {
	int adjusted_vtemp = ts * ST_VREFINT_CAL / vref;
	int slope = (110-30) / (ST_TSENSE_CAL2_110C - ST_TSENSE_CAL1_30C);
	return slope * (adjusted_vtemp - ST_TSENSE_CAL1_30C) + 30;
}

void adc_power_task_up(void) {
	TIM_CNT(TIMER) = 0;
	adc_power_on(ADC1);
	unsigned int td = TIM_CNT(TIMER);
	
	/* just for kicks, let's time some sequences too....
	 * I mean, we're going to do some conversions right? */
	adc_set_single_conversion_mode(ADC1);
	TIM_CNT(TIMER) = 0;
	unsigned int v1 = read_adc_naiive(1); // 8 for l4!
	unsigned int v5 = read_adc_naiive(5);
	unsigned int temp_adc = read_adc_naiive(ADC_CHANNEL_TEMP);
	unsigned int vref_adc = read_adc_naiive(ADC_CHANNEL_VREF);
	unsigned int tconv = TIM_CNT(TIMER);
	TIM_CNT(TIMER) = 0;
	float tempf = adc_calc_tempf(temp_adc, vref_adc);
	int tconvf = TIM_CNT(TIMER);
	TIM_CNT(TIMER) = 0;
	int tempi = adc_calc_tempi(temp_adc, vref_adc);
	int tconvi = TIM_CNT(TIMER);
	
	printf("ton: %u, tconv: %u, ch1: %u, ch5: %u\n", td, tconv, v1, v5);
	printf("\tTemperature: %f (tc %d) or %d (tc %d) (raw ts: %d, raw vref: %d)\n",
		tempf, tconvf, tempi, tconvi, temp_adc, vref_adc);
	//printf("\tT1-30 %d, t2-110 %d, vrefcal: %d\n", ST_TSENSE_CAL1_30C, ST_TSENSE_CAL2_110C, ST_VREFINT_CAL);
}

void adc_power_task_down()
{
	TIM_CNT(TIMER) = 0;
	adc_power_off(ADC1);
	unsigned int td = TIM_CNT(TIMER);
	printf("toff in: %u\n", td);
}