Feature/p3t1755 (#379)

Co-authored-by: Caio DaSilva <dasilva.cai@northeastern.edu>

Author: aolgeirson

general/include/p3t1755.h

@@ -5,18 +5,22 @@
 
 #ifndef p3t1755_H
 #define p3t1755_H
-#include <stdint.h>
 #include <math.h>
+#include <stdint.h>
 
 // REGISTERS
-// Temperature register: contains two 8-bit data bytes; to store the measured Temp data.
+// Temperature register: contains two 8-bit data bytes; to store the measured
+// Temp data.
 #define p3t1755_TEMPERATURE 0x00 // read only
-// Configuration register: contains a single 8-bit data byte; to set the device operating condition
+// Configuration register: contains a single 8-bit data byte; to set the device
+// operating condition
 #define p3t1755_CONFIGURATION 0x01
-// T_low register: Hysteresis register, it contains two 8-bit data bytes to store the hysteresis T_low limit; default = 75 °C.
+// T_low register: Hysteresis register, it contains two 8-bit data bytes to
+// store the hysteresis T_low limit; default = 75 °C.
 #define p3t1755_T_LOW 0x02
-// T_high register: Overtemperature shut down threshold register, it contains two 8-bit data bytes to
-// store the overtemperature shutdown T_high limit; default = 80 °C.
+// T_high register: Overtemperature shut down threshold register, it contains
+// two 8-bit data bytes to store the overtemperature shutdown T_high limit;
+// default = 80 °C.
 #define p3t1755_T_HIGH 0x03
 
 // TEMPERATURE REGISTER FORMAT
@@ -61,6 +65,8 @@ typedef struct {
 	ReadPtr read;
 } p3t1755_t;
 
+float p3t1755_raw_to_celsius(uint16_t raw);
+
 void p3t1755_init(p3t1755_t *p3t, WritePtr write, ReadPtr read,
 		  uint16_t dev_addr);
 
@@ -90,4 +96,4 @@ int p3t1755_read_low_temp(p3t1755_t *p3t, float *temp_c);
 int p3t1755_set_high_temp(p3t1755_t *p3t, float temp_c);
 int p3t1755_set_low_temp(p3t1755_t *p3t, float temp_c);
 
-#endif
+#endif

general/src/p3t1755.c

@@ -5,13 +5,15 @@
 
 #include "p3t1755.h"
 #include "c_utils.h"
+#include "u_tx_debug.h"
+#include <stdint.h>
 
 void p3t1755_init(p3t1755_t *p3t, WritePtr write, ReadPtr read,
 		  uint16_t dev_addr)
 {
 	p3t->write = write;
 	p3t->read = read;
-	p3t->dev_addr = dev_addr;
+	p3t->dev_addr = dev_addr << 1;
 }
 
 int p3t1755_write_reg(p3t1755_t *p3t, uint16_t reg, uint8_t *data,
@@ -26,6 +28,15 @@ int p3t1755_read_reg(p3t1755_t *p3t, uint16_t reg, uint8_t *data,
 	return p3t->read(p3t->dev_addr, reg, data, length);
 }
 
+inline float p3t1755_raw_to_celsius(uint16_t raw)
+{
+	PRINTLN_INFO("raw temp: %d", raw);
+	if (raw & 1 << 11) { // Check if sign bit is set |-> t<0
+		return -(raw * p3t1755_TEMP_RESOLUTION);
+	} else
+		return (raw * p3t1755_TEMP_RESOLUTION);
+}
+
 int p3t1755_read_temperature(p3t1755_t *p3t, float *temp_c)
 {
 	uint8_t temp_reg[2];
@@ -36,8 +47,8 @@ int p3t1755_read_temperature(p3t1755_t *p3t, float *temp_c)
 		return status;
 	}
 
-	*temp_c = p3t1755_RAW_TO_CELSIUS(
-		uint8_to_uint16(temp_reg[0], temp_reg[1]));
+	*temp_c = p3t1755_raw_to_celsius(
+		uint8_to_uint16(temp_reg[0] >> 4, temp_reg[1] >> 4));
 	return status;
 }
 
@@ -225,4 +236,4 @@ int p3t1755_set_low_temp(p3t1755_t *p3t, float temp_c)
 
 	return p3t1755_write_reg(p3t, p3t1755_T_LOW, temp_data,
 				 sizeof(temp_data));
-}
+}