From d97ecd3a2976ff4541bc8d4af9cbadfb245dbcef Mon Sep 17 00:00:00 2001
From: guowenxue <guowenxue@gmail.com>
Date: Mon, 06 Jul 2026 23:39:51 +0800
Subject: [PATCH] Add ex1.auto-light demo code
---
ex1.buzzer-music/Board/miscdev.c | 68 +++++++++++++++++++++++++++++++++-
1 files changed, 66 insertions(+), 2 deletions(-)
diff --git a/ex1.buzzer-music/Board/miscdev.c b/ex1.buzzer-music/Board/miscdev.c
index 73c7a4a..e2d294d 100644
--- a/ex1.buzzer-music/Board/miscdev.c
+++ b/ex1.buzzer-music/Board/miscdev.c
@@ -268,6 +268,70 @@
return 0;
}
+/* ------------------- Lux 滤波相关参数 ------------------- */
+#define LUX_SAMPLE_COUNT 10 /* 每次采集的原始样本数 */
+#define LUX_TRIM_COUNT 2 /* 排序后，头尾各丢弃的样本数 */
+
+/**
+ * @brief 简单冒泡排序（数据量很小，不追求性能）
+ */
+static void sort_u32(uint32_t *arr, int n)
+{
+ for (int i = 0; i < n - 1; i++)
+ {
+ for (int j = 0; j < n - 1 - i; j++)
+ {
+ if (arr[j] > arr[j + 1])
+ {
+ uint32_t tmp = arr[j];
+ arr[j] = arr[j + 1];
+ arr[j + 1] = tmp;
+ }
+ }
+ }
+}
+
+/**
+ * @brief 多次采样光照度ADC值，排序后去掉两端的离群样本，再取平均
+ * @param lux: 输出参数，滤波后的光照度值
+ * @retval 0 成功, -1 失败
+ */
+static int adc_read_lux_filtered(uint32_t *lux)
+{
+ uint32_t samples[LUX_SAMPLE_COUNT];
+ uint32_t sum = 0;
+ int valid_count;
+
+ /* 多次采样光照度ADC值 */
+ for (int i = 0; i < LUX_SAMPLE_COUNT; i++)
+ {
+ if (adc_read_channel(ADC_CHANNEL_15, &samples[i]) != 0)
+ return -1;
+ }
+
+ /* 将多次采样的数据排序 */
+ sort_u32(samples, LUX_SAMPLE_COUNT);
+
+ /* 丢弃排序后头尾各 LUX_TRIM_COUNT 个可能的离群值 */
+ valid_count = LUX_SAMPLE_COUNT - 2 * LUX_TRIM_COUNT;
+ if (valid_count <= 0)
+ {
+ /* 参数配置不合理时兜底，避免除0 */
+ valid_count = LUX_SAMPLE_COUNT;
+ for (int i = 0; i < LUX_SAMPLE_COUNT; i++)
+ sum += samples[i];
+ }
+ else
+ {
+ for (int i = LUX_TRIM_COUNT; i < LUX_SAMPLE_COUNT - LUX_TRIM_COUNT; i++)
+ sum += samples[i];
+ }
+
+ *lux = sum / valid_count;
+
+ return 0;
+}
+
/**
* @brief 采集光照度与噪声值
* @param lux: 输出参数，采集到的光照度值
@@ -276,11 +340,11 @@
*/
int adc_sample_lux_noisy(uint32_t *lux, uint32_t *noisy)
{
- if (adc_read_channel(ADC_CHANNEL_15, lux) != 0)
+ if (adc_read_lux_filtered(lux) != 0)
return -1;
if (adc_read_noisy_peak(noisy, 50) != 0)
- return -1;
+ return -2;
return 0;
}
--
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