小熊派BearPi-Pico H2821星闪开发板测评（三）——ADC与DMA测试

FuShenxiao 发表于 2024-8-12 16:04

ADC采样测试

对于H2821，GPIO02和GPIO03可复用为模拟电压输入，因此将这两个引脚接入电位器用于ADC采样测试。

  

代码实现：

<pre>
<code>#include "pinctrl.h"
#include "gpio.h"
#include "adc.h"
#include "adc_porting.h"
#include "osal_debug.h"
#include "cmsis_os2.h"
#include "app_init.h"
#include "pm_pmu.h"

#define ADC_TASK_STACK_SIZE 0x1000
#define ADC_TASK_PRIO (osPriority_t)(17)
#define ADC_AUTO_SAMPLE_TEST_TIMES 1000

#define GAFE_SAMPLE_VALUE_SIGN_BIT 17
#define ADC_REFERENCE_VOLTAGE_MV 1500
#define ADC_REF_VOL_DIFFERENCE_MULT 2
#define ADC_TICK2VOL_REF_VOLTAGE_MV (ADC_REFERENCE_VOLTAGE_MV * ADC_REF_VOL_DIFFERENCE_MULT)

static void adc_set_io(uint8_t channel)
{
pin_t adc_pin[] = {S_MGPIO2, S_MGPIO3, S_MGPIO4, S_MGPIO5, S_MGPIO28, S_MGPIO29, S_MGPIO30, S_MGPIO31};

uapi_pin_set_mode(adc_pin, PIN_MODE_0);
uapi_gpio_set_dir(adc_pin, GPIO_DIRECTION_INPUT);
uapi_pin_set_pull(adc_pin, PIN_PULL_NONE);
#if defined(CONFIG_PINCTRL_SUPPORT_IE)
uapi_pin_set_ie(adc_pin, PIN_IE_1);
#endif
}

static void *adc_task(const char *arg)
{
UNUSED(arg);

uapi_pmu_control(PMU_CONTROL_MICLDO_POWER, PMU_CONTROL_POWER_ON);
uapi_pmu_ldo_set_voltage(PMU_LDO_ID_MICLDO, PMU_MICLDO_VSET_1V5);//在MLDO脚产生一个1.5V的电压便以测试
osal_printk("start adc sample test\n");
uapi_adc_init(ADC_CLOCK_NONE);
adc_set_io(GADC_CHANNEL_0);
uapi_adc_open_channel(GADC_CHANNEL_0);//GPIO02
uapi_adc_power_en(AFE_GADC_MODE, true);
adc_calibration(AFE_GADC_MODE, true, true, true);

while (1)
{
 int gadc_value = 0;
 gadc_value =uapi_adc_auto_sample(GADC_CHANNEL_0);
 osal_printk("gadc: %dmv\n\n", (gadc_value * ADC_TICK2VOL_REF_VOLTAGE_MV) >> GAFE_SAMPLE_VALUE_SIGN_BIT);
 osDelay(2000);
}
return NULL;
}

static void adc_entry(void)
{
osThreadAttr_t attr;

attr.name = "ADCTask";
attr.attr_bits = 0U;
attr.cb_mem = NULL;
attr.cb_size = 0U;
attr.stack_mem = NULL;
attr.stack_size = ADC_TASK_STACK_SIZE;
attr.priority = ADC_TASK_PRIO;

if (osThreadNew((osThreadFunc_t)adc_task, NULL, &attr) == NULL) {
 /* Create task fail. */
}
}

/* Run the adc_entry. */
app_run(adc_entry);
</code></pre>

其中

uapi_pmu_control用于使能LDO

uapi_pmu_ldo_set_voltage用于使MIC_LDO引脚产生一个指定的电压（可以产生标准的1.1V，1.3V，1.5V，1.8V，2.0V，2.2V，2.5V，2.8V电压）用于测试

  

得到串口输出



可见在电位器的控制下，电压逐渐升高

特别的，当电压高于1.5V时，ADC的值将不再变化，观察ADC值的计算方法，发现

gadc = gadc_value * ADC_TICK2VOL_REF_VOLTAGE_MV) >> GAFE_SAMPLE_VALUE_SIGN_BIT

其中

gadc_value为ADC接口测量值

ADC_TICK2VOL_REF_VOLTAGE_MV为基准值，宏定义为3000

GAFE_SAMPLE_VALUE_SIGN_BIT为右移位数，宏定义为17

虽然这个表达式并不能看出芯片对ADC电压的限制，但实际电路应该是对ADC输入做了限制，因为就算我调整了基准电压值，最大有效输入电压仍为1.5V

除此之外，对比万用表测量输入电压和ADC采样得到的值，ADC采样结果相较万用表小了大约50mV，因此实际程序运行时可能需要多加注意并进行修正

 

为了实现多路ADC采样，需要在主函数循环部分的每次采样前都打开采样通道

  

若没有在循环部分中打开采样通道，两路ADC采样的结果都将取决于编号较大的模拟采样通道（比如GPIO02的模拟采样通道是AIN0，GPIO03的模拟采样通道是AIN1，如果不打开采样通道就进行采样，AIN0和AIN1的采样结果都将取决于AIN1）。当然，对于单个ADC采样而言，在循环体中是否打开采样通道是无所谓的，仅需在初始化时打开即可。

代码实现：

<pre>
<code>#include "pinctrl.h"
#include "gpio.h"
#include "adc.h"
#include "adc_porting.h"
#include "osal_debug.h"
#include "cmsis_os2.h"
#include "app_init.h"
#include "pm_pmu.h"

#define ADC_TASK_STACK_SIZE 0x1000
#define ADC_TASK_PRIO (osPriority_t)(17)
#define ADC_AUTO_SAMPLE_TEST_TIMES 1000

#define GAFE_SAMPLE_VALUE_SIGN_BIT 17
#define ADC_REFERENCE_VOLTAGE_MV 1500
#define ADC_REF_VOL_DIFFERENCE_MULT 2
#define ADC_TICK2VOL_REF_VOLTAGE_MV (ADC_REFERENCE_VOLTAGE_MV * ADC_REF_VOL_DIFFERENCE_MULT)

static void adc_set_io(uint8_t channel)
{
pin_t adc_pin[] = {S_MGPIO2, S_MGPIO3, S_MGPIO4, S_MGPIO5, S_MGPIO28, S_MGPIO29, S_MGPIO30, S_MGPIO31};
uapi_pin_set_mode(adc_pin, PIN_MODE_0);
uapi_gpio_set_dir(adc_pin, GPIO_DIRECTION_INPUT);
uapi_pin_set_pull(adc_pin, PIN_PULL_NONE);
#if defined(CONFIG_PINCTRL_SUPPORT_IE)
uapi_pin_set_ie(adc_pin, PIN_IE_1);
#endif
}

static void *adc_task(const char *arg)
{
UNUSED(arg);

uapi_pmu_control(PMU_CONTROL_MICLDO_POWER, PMU_CONTROL_POWER_ON);
uapi_pmu_ldo_set_voltage(PMU_LDO_ID_MICLDO, PMU_MICLDO_VSET_1V5);//在MLDO脚产生一个1.5V的电压便以测试
osal_printk("start adc sample test\n");
uapi_adc_init(ADC_CLOCK_NONE);
adc_set_io(GADC_CHANNEL_0);
adc_set_io(GADC_CHANNEL_1);
uapi_adc_open_channel(GADC_CHANNEL_0);//GPIO02
uapi_adc_open_channel(GADC_CHANNEL_1);//GPIO03
uapi_adc_power_en(AFE_GADC_MODE, true);
adc_calibration(AFE_GADC_MODE, true, true, true);

while (1)
{
 int gadc_value1 = 0;
 int gadc_value2 = 0;
 uapi_adc_open_channel(GADC_CHANNEL_0);//GPIO02
 gadc_value1 =uapi_adc_auto_sample(GADC_CHANNEL_0);
 uapi_adc_open_channel(GADC_CHANNEL_1);//GPIO03
 gadc_value2 = uapi_adc_auto_sample(GADC_CHANNEL_1);
 osal_printk("gadc1: %dmv\n\n", (gadc_value1 * ADC_TICK2VOL_REF_VOLTAGE_MV) >> GAFE_SAMPLE_VALUE_SIGN_BIT);
 osal_printk("gadc2: %dmv\n\n", (gadc_value2 * ADC_TICK2VOL_REF_VOLTAGE_MV) >> GAFE_SAMPLE_VALUE_SIGN_BIT);
 osDelay(2000);
}
return NULL;
}

static void adc_entry(void)
{
osThreadAttr_t attr;

attr.name = "ADCTask";
attr.attr_bits = 0U;
attr.cb_mem = NULL;
attr.cb_size = 0U;
attr.stack_mem = NULL;
attr.stack_size = ADC_TASK_STACK_SIZE;
attr.priority = ADC_TASK_PRIO;

if (osThreadNew((osThreadFunc_t)adc_task, NULL, &attr) == NULL) {
 /* Create task fail. */
}
}

/* Run the adc_entry. */
app_run(adc_entry);
</code></pre>

输出结果：

  

DMA内存访问测试

DAM用于内存数据的搬运，从而减少CPU的负担

代码实现如下：

<pre>
<code>#include "securec.h"
#include "common_def.h"
#include "dma.h"
#include "hal_dma.h"
#include "dma_porting.h"
#include "osal_debug.h"
#include "cmsis_os2.h"
#include "app_init.h"

#define DMA_TRANSFER_WORD_NUM 32
#define DMA_TRANSFER_PRIORITY 0
#define DMA_TRANSFER_WIDTH 2

#define DMA_TASK_STACK_SIZE 0x1000
#define DMA_TASK_DURATION_MS 500
#define DMA_TASK_PRIO (osPriority_t)(17)

static uint32_t g_app_dma_src_data = { 0 };
static uint32_t g_app_dma_desc_data = { 0 };
static uint8_t g_dma_trans_done = 0;

static void app_dma_trans_done_callback(uint8_t int_type, uint8_t channel, uintptr_t arg)
{
unused(arg);
unused(channel);
switch (int_type) {
 case HAL_DMA_INTERRUPT_TFR:
 g_dma_trans_done = 1;
 break;
 case HAL_DMA_INTERRUPT_BLOCK:
 g_dma_trans_done = 1;
 break;
 case HAL_DMA_INTERRUPT_ERR:
 osal_printk("DMA transfer error.\r\n");
 break;
 default:
 break;
}
}

static void *dma_task(const char *arg)
{
unused(arg);
/* DMA init. */
dma_port_clock_enable();
uapi_dma_init();
uapi_dma_open();

#if defined(CONFIG_DMA_MEMORY_LLI_TRANSFER_MODE)
dma_channel_t dma_channel = DMA_CHANNEL_NONE;
dma_channel = uapi_dma_get_lli_channel(0, HAL_DMA_HANDSHAKING_MAX_NUM);
#endif

for (uint32_t i = 0; i < DMA_TRANSFER_WORD_NUM; i++) {
 g_app_dma_src_data = i;
}
memset_s(g_app_dma_desc_data, DMA_TRANSFER_WORD_NUM, 0, DMA_TRANSFER_WORD_NUM);

dma_ch_user_memory_config_t transfer_config = { 0 };
transfer_config.src = (uint32_t)(uintptr_t)g_app_dma_src_data;
transfer_config.dest = (uint32_t)(uintptr_t)g_app_dma_desc_data;
transfer_config.transfer_num = DMA_TRANSFER_WORD_NUM;
transfer_config.priority = DMA_TRANSFER_PRIORITY;
transfer_config.width = DMA_TRANSFER_WIDTH;

while (1) {
 osDelay(DMA_TASK_DURATION_MS);
 g_dma_trans_done = 0;
#if defined(CONFIG_DMA_MEMORY_LLI_TRANSFER_MODE)
 osal_printk("dma config link list item of memory to memory start!\r\n");
 if (uapi_dma_transfer_memory_lli(dma_channel, &transfer_config, app_dma_trans_done_callback) == ERRCODE_SUCC) {
 osal_printk("dma config link list item of memory to memory succ!\r\n");
 }
 osal_printk("dma enable lli memory transfer start!\r\n");
 if (uapi_dma_enable_lli(dma_channel, app_dma_trans_done_callback, (uintptr_t)NULL) == ERRCODE_SUCC) {
 osal_printk("dma enable lli memory transfer succ!\r\n");
 }
 while (!g_dma_trans_done) {}
 if (uapi_dma_end_transfer(dma_channel) == ERRCODE_SUCC) {
 osal_printk("dma channel transfer finish!\r\n");
 }
#else
 osal_printk("dma single memory transfer start!\r\n");
 if (uapi_dma_transfer_memory_single(&transfer_config, app_dma_trans_done_callback,
 (uintptr_t)NULL) == ERRCODE_SUCC) {
 osal_printk("dma single memory transfer succ!\r\n");
 }
 while (!g_dma_trans_done) {}
 osal_printk("dma checking transfer from 0x%08x to 0x%08x...\r\n", transfer_config.src, transfer_config.dest);
 if (memcmp((void *)transfer_config.src, (void *)transfer_config.dest, transfer_config.transfer_num) == 0) {
 osal_printk("dma memory copy test succ, length = %d block\r\n", transfer_config.transfer_num);
 }
#endif
}

return NULL;
}

static void dma_entry(void)
{
osThreadAttr_t attr;

attr.name = "DmaTask";
attr.attr_bits = 0U;
attr.cb_mem = NULL;
attr.cb_size = 0U;
attr.stack_mem = NULL;
attr.stack_size = DMA_TASK_STACK_SIZE;
attr.priority = DMA_TASK_PRIO;

if (osThreadNew((osThreadFunc_t)dma_task, NULL, &attr) == NULL) {
 /* Create task fail. */
}
}

/* Run the dma_entry. */
app_run(dma_entry);
</code></pre>

结果显示：

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小熊派BearPi-Pico H2821星闪开发板测评（三）——ADC与DMA测试