therm Changeset - b41e2aea6dd8 · protofusion repositories

Changeset - b41e2aea6dd8

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cortex-f0

0 2 0

matthewreed - 8 years ago 2015-12-23 20:45:16

Added correct temperature conversions to RTD version

2 files changed with 38 insertions and 19 deletions:

display.c

max31865.c

0 comments (0 inline, 0 general)

display.c

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@@ @@ -24,6 +24,7 @@ static uint8_t sw_right_last = 0; @@
 // States
 static uint8_t trigger_drawsetpoint = 1;
 static int16_t last_temp = 21245;
 static int16_t last_state = STATE_IDLE;
 static uint8_t goto_mode = MODE_HEAT;
 static uint8_t reset_mode = RESET_REBOOT;
@@ @@ -32,7 +33,8 @@ static uint8_t reset_mode = RESET_REBOOT @@
 // Display state machine
 void display_process(therm_settings_t* set, therm_status_t* status)
+{
     uint8_t last_state = status->state;
     uint8_t state_changed = status->state != last_state;
     last_state = status->state;
     uint8_t temp_changed = status->temp != last_temp;
     last_temp = status->temp;
@@ @@ -53,7 +55,7 @@ void display_process(therm_settings_t* s @@
             ssd1306_drawstring("therm :: idle ", 0, 40);
             status->pid_enabled = 0;
             if(temp_changed) {
+            if(temp_changed || state_changed) {
                 char tempstr[6];
                 itoa_fp(status->temp, status->temp_frac, tempstr);
                 ssd1306_drawstring("Temp: ", 3, 40);
@@ @@ -61,7 +63,9 @@ void display_process(therm_settings_t* s @@
                 ssd1306_drawstring(tempstr, 3, 72);
+            }
             ssd1306_drawlogo();
             if (state_changed) {
             	ssd1306_drawlogo();
+            }
             switch(goto_mode) {

max31865.c

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@@ @@ -61,8 +61,6 @@ void max31865_readtemp(SPI_HandleTypeDef @@
         // 2-wire RTC or 2-wire (duh) NTC thermistor will be the only options
         // Need option for resistance of RTD
         // These options should be stored in the set structure and should be menu-selectable
     // TODO: Read RTD msbs (0x01)
     // TODO: Read RTD LSBs (0x02)
     // Assert CS
     HAL_GPIO_WritePin(MAX_CS, 0);
@@ @@ -80,7 +78,7 @@ void max31865_readtemp(SPI_HandleTypeDef @@
     HAL_GPIO_WritePin(MAX_CS, 1);
     // Assemble data array into one var
-    uint16_t temp_pre = (rxdatah[0]<<8) | rxdatal[0];
+    uint16_t adc_count = ((rxdatah[0] & 0x7F) << 8) | rxdatal[0];
     if((rxdatah[0] & 0x80) && !set->val.ignore_error) {
@@ @@ -89,7 +87,7 @@ void max31865_readtemp(SPI_HandleTypeDef @@
         uint8_t reg = MAX31865_REG_FAULTSTATUS;
-        uint8_t data[1] = {0x11};
+        uint8_t data[1] = {0x00};
         HAL_SPI_Transmit(hspi1, &reg, 1, 100);
         HAL_SPI_Receive(hspi1, data, 1, 100);
@@ @@ -108,31 +106,48 @@ void max31865_readtemp(SPI_HandleTypeDef @@
+    }
     else
+    {
         // Convert to decimal
         //temp_pre = temp_pre >> 1;
         uint16_t adc_count = temp_pre & 0x7FFF; //do some scaling?
         // Convert to Fahrenheit
         if(set->val.temp_units == TEMP_UNITS_FAHRENHEIT)
+        {
             status->temp = adc_count;
             //convert to fahrenheit
         	//use all fixed point math!
         	//convert adc to resistance
         	//Rrtd = adc / range * Rref
         	status->temp = adc_count * 9830 * 10;
         	status->temp /= 32768;
         	//resistance to temp
         	//(x - in1) * (cal2 - cal1) / (in2 - in1) + cal1
         	status->temp = ((status->temp * 100) - 100000) * (39200 - 3200) / (175860 - 100000) + 3200;
         	//grab the fraction
         	status->temp_frac = (status->temp / 10) % 10;
         	//scale back to degrees
         	status->temp = status->temp / 100;
         	//add in the offset
             status->temp += set->val.temp_offset;
+        }
-        // Use Celsius values
+        // Convert to Celsius
         else
+        {
             //convert to celsius
             int32_t temp = (((int32_t) adc_count) / 32) - 256;
             status->temp = temp;
         	//use all fixed point math!
         	//convert adc to resistance
         	//Rrtd = adc / range * Rref
         	status->temp = adc_count * 9830 * 10;
         	status->temp /= 32768;
         	//resistance to temp
         	//(x - in1) * (cal2 - cal1) / (in2 - in1) + cal1
         	status->temp = ((status->temp * 10) - 10000) * (20000 - 0) / (17586 - 10000) + 0;
         	//grab the fraction
         	status->temp_frac = (status->temp / 10) % 10;
         	//scale back to degrees
         	status->temp = status->temp / 100;
         	//add in the offset
             status->temp += set->val.temp_offset;
+        }
+    }
+}
 // vim:softtabstop=4 shiftwidth=4 expandtab

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