mov det temperature sample from internal ADC to LTC1867

lark1fq/src/CMakeLists.txt

@@ -2,6 +2,8 @@ include_directories(.)
 include_directories(../../driver/stddriver/inc)
 include_directories(../../driver/cmsis/inc)
 
+add_definitions(-DDET_TEMPERATURE_LTC1867)
+
 file(GLOB FILELIST
 device.c
 user_misc.c

lark1fq/src/adc.c

@@ -14,6 +14,7 @@ A3 = 7.7743300e-8*/
 static float Ncp15wCoeff[4] = {2.3088245e-3, 2.1731924e-4, 1.7282124e-6, 7.7743300e-8};
 static uint16_t adc_data[4][12] __attribute__((section(".bss_ccm")));
 static uint16_t adc_data_sort[12] __attribute__((section(".bss_ccm")));
+uint16_t adc_det_temp_from_ltc1867 __attribute__((section(".bss_ccm")));
 
 float adc_to_resistance(uint16_t adc_value)
 {
@@ -25,6 +26,16 @@ float adc_to_resistance(uint16_t adc_value)
     return (float)value1 / (float)value2;
 }
 
+float adc_to_resistance16(uint16_t adc_value)
+{
+    uint32_t value1, value2;
+
+    value1 = 100 * (uint32_t)adc_value;
+    value2 = 65536 - (uint32_t)adc_value;
+
+    return (float)value1 / (float)value2;
+}
+
 uint32_t adc_rtot(uint16_t adc_value)
 {
     int i = 0;
@@ -42,6 +53,23 @@ uint32_t adc_rtot(uint16_t adc_value)
     return (uint32_t)t;
 }
 
+uint32_t adc_rtot16(uint16_t adc_value)
+{
+    int i = 0;
+    float t = 0;
+    float rtemp;
+    
+    rtemp = adc_to_resistance16(adc_value);
+    rtemp = logf(rtemp);
+    
+    for(i = 3; i >= 0; i--) {
+        t = t * rtemp + Ncp15wCoeff[i];
+    }
+    t = 100.0f / t; /* unit: 0.01K */
+
+    return (uint32_t)t;
+}
+
 void adc_input_data(uint8_t ch, uint16_t data)
 {
     static uint8_t idx[4] = {0, 0, 0, 0};
@@ -56,7 +84,7 @@ void adc_input_data(uint8_t ch, uint16_t data)
 uint16_t adc_get_filter_data(uint8_t ch)
 {
     uint32_t i, j, min_idx;
-    uint16_t sum;
+    uint32_t sum;
 
     /* copy data to buffer */
     for (i = 0; i < ADC_FILTER_LEN - 1; i++) {
@@ -81,8 +109,8 @@ uint16_t adc_get_filter_data(uint8_t ch)
     for (i = 2; i < ADC_FILTER_LEN - 2; i++) {
         sum += adc_data_sort[i];
     }
-    sum = (sum + 4) / (ADC_FILTER_LEN - 4);
+    sum = (sum + (ADC_FILTER_LEN - 4) / 2) / (ADC_FILTER_LEN - 4);
-    return sum;
+    return (uint16_t)sum;
 }
 
 void adc_init(void)
@@ -142,10 +170,20 @@ void adc_loop(void)
     }
     ms = system_tick_cnt;
     val = adc_read();
+#ifdef DET_TEMPERATURE_LTC1867
+    if (ch == 0) {
+        val = adc_det_temp_from_ltc1867;
+    }
+#endif
     debug_write_data(20 + ch, (float)val);
     adc_input_data(ch, val); /* input data from ADC to sort buffer */
     if (ch == 0) {
         val = adc_get_filter_data(ch);
+#ifdef DET_TEMPERATURE_LTC1867
+        value = adc_rtot16(val);
+#else
+        value = adc_rtot(val);
+#endif
         value = adc_rtot(val);
         debug_write_data(24 + ch, (float)value);
         device_data.detector_temperature = value;

lark1fq/src/adc.h

@@ -12,7 +12,9 @@
 extern uint32_t system_tick_cnt;
 
 float adc_to_resistance(uint16_t adc_value);
+float adc_to_resistance16(uint16_t adc_value);
 uint32_t adc_rtot(uint16_t adc_value);
+uint32_t adc_rtot16(uint16_t adc_value);
 void adc_input_data(uint8_t ch, uint16_t data);
 uint16_t adc_get_filter_data(uint8_t ch);
 void adc_init(void);

lark1fq/src/ltc1867.c

@@ -13,7 +13,7 @@
 #define diff32768(data) ((data > 32768) ? (data - 32768) : (32768 - data))
 
 struct data_ltc1867_s data_ltc1867 __attribute__((section(".bss_ccm")));
-static const uint16_t ltc1867_spi_data[4] = {0xC400, 0x9400, 0xD400, 0x8400}; /* order: ch1, ch2, ch3, ch0 */
+static const uint16_t ltc1867_spi_data[LTC1867_CH_CNT] = {0xC400, 0x9400, 0xD400, 0xA400, 0x8400}; /* order: ch1, ch2, ch3, ch4, ch0 */
 
 void ltc1867_init(void)
 {
@@ -98,7 +98,7 @@ void ltc1867_init(void)
     SPI_Init(SPI1, &SPI_InitStructure);
     SPI_Cmd(SPI1, ENABLE);
     ltc1867_spi_select();
-    ltc1867_transfer(ltc1867_spi_data[3]);
+    ltc1867_transfer(ltc1867_spi_data[LTC1867_CH_CNT - 1]);
 
     /* data_ltc1867 init */
     data_ltc1867.sum[0] = 0;    /* store temporary sum of half period sum */
@@ -175,7 +175,7 @@ uint16_t ltc1867_transfer(uint16_t data_send)
 
 void TIM2_IRQHandler(void)
 {
-    uint16_t val[4];
+    uint16_t val[LTC1867_CH_CNT];
 
     TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
 
@@ -188,8 +188,8 @@ void TIM2_IRQHandler(void)
         data_ltc1867.ledir_cnt = 0;
     }
 
-    /* sample 4 channel adc data */
+    /* sample 5 channel adc data */
-    for (uint8_t i = 0; i < 4; i++) {
+    for (uint8_t i = 0; i < LTC1867_CH_CNT; i++) {
         ltc1867_conv(); /* this point start convert */
         ltc1867_delay(); /* delay 3.5us for convert time, reference for LTC1867 datasheet */
         ltc1867_spi_select(); /* convert complete, make convert pin low for reading sample data by SPI */
@@ -198,8 +198,9 @@ void TIM2_IRQHandler(void)
     /* split 2 for loop, because sample timing is strict, only place important code in sample duration */
     for (uint8_t i = 0; i < 4; i++) {
         data_ltc1867.sum[i] += diff32768(val[i]); /* add every channel original data for next process */
-        debug_write_data(i, (float)val[i]); /* channel 1~4 for ltc1867 original sample data */
+        debug_write_data(i, (float)val[i]); /* channel 0~3 for ltc1867 original sample data */
     }
+    adc_det_temp_from_ltc1867 = val[4]; /* channel 4 for ltc1867 detector temperature sample data */
     data_ltc1867.val_idx++;
     if ((data_ltc1867.val_idx >= CALC_CNT) && (data_ltc1867.locked != 0)) {
         data_ltc1867.val_idx = 0;

lark1fq/src/ltc1867.h

@@ -12,6 +12,8 @@
 #define TIMER_PERIOD_SAMPLE (TIMER_SRC_FREQ / LEDIR_FREQ / SAMPLES_PER_PERIOD - 1)
 #define TIMER_PERIOD_DELAY  (TIMER_SRC_FREQ / 1000 / 1000 * 35 / 10 - 1)  /* 3.5us */
 
+#define LTC1867_CH_CNT      (5)
+
 #define PORT_LEDIR          (GPIOB)
 #define PIN_LEDIR           (GPIO_Pin_0)
 #define PORT_LTC1867        (GPIOA)
@@ -32,6 +34,7 @@ struct data_ltc1867_s {
 };
 
 extern struct data_ltc1867_s data_ltc1867;
+extern uint16_t adc_det_temp_from_ltc1867;
 
 void ltc1867_init(void);
 void ltc1867_ledir_on(void);