applied suggested changes - thanks for the feedback

Author: Louis31423142

i2c/ina228_i2c/README.md i2c/ina228_i2c/README.adoci2c/ina228_i2c/README.md renamed to i2c/ina228_i2c/README.adoc

@@ -14,7 +14,7 @@ The INA228 is highly configurable. Find the datasheet online (https://www.ti.com
 [[bmp280_i2c_wiring]]
 [pdfwidth=75%]
 .Wiring Diagram for BMP280 sensor via I2C.
-image::bmp280_i2c_bb.png[]
+image::ina228_i2c.png[]
 
 == List of Files
 

i2c/ina228_i2c/ina228_i2c.c

@@ -6,13 +6,19 @@
 // LED GPIOs
 #define EXT_LED_GPIO 2
 
-// INA228 integrated shunt resistance
+// INA228 integrated shunt resistance in Ohms
 #define R_SHUNT 0.015
 
-// Max expected current through shunt resistor
+// Max expected current through shunt resistor in Amps
 #define MAX_EXPECTED_CURRENT 0.1
 #define I2C_ADDR 0x40
 
+// Macros for bit-shifting register reads
+#define FLATTEN2(a2) ((a2[0] << 8) + a2[1])
+#define FLATTEN3(a3) ((a3[0] << 16) | (a3[1] << 8) | a3[2])
+#define FLATTEN3_RESERVED(a3) ((a3[0] << 12) | (a3[1] << 4) | (a3[2] >> 4))
+#define FLATTEN5(a5) (((uint64_t) a5[0] << 32) | (a5[1] << 24) | (a5[2] << 16) | (a5[3] << 8) | a5[4])
+
 // ina228 registers (see datasheet)
 uint8_t VSHUNT_REG = 0x04;
 uint8_t VBUS_REG = 0x05;
@@ -42,11 +48,11 @@ float vshunt, vbus, dietemp, current, power, energy, charge;
 static void ina228_init() {
     // Write to shunt register 
     uint8_t shunt_msb = (SHUNT_CAL >> 8) & 0xFF;
-    uint8_t shunt_lsb = SHUNT_CAL & 0xff;
+    uint8_t shunt_lsb = SHUNT_CAL & 0xFF;
     uint8_t shunt_buf[3] = {SHUNT_CAL_REG, shunt_msb, shunt_lsb};
     i2c_write_blocking(i2c_default, I2C_ADDR, shunt_buf, 3, false);
 
-    // Write to ADC config register (need to enable continuous mode to access accumilation variables energy and charge)
+    // Write to ADC config register (need to enable continuous mode to access accumulation variables energy and charge)
     uint8_t adc_msb = 0xF0;
     uint8_t adc_lsb = 0x00;
     uint8_t adc_buf[3] = {ADC_CONFIG_REG, adc_msb, adc_lsb};
@@ -55,39 +61,39 @@ static void ina228_init() {
 
 static void ina228_read(float *vshunt, float *vbus, float *dietemp, float *current, float *power, float *energy, float *charge) {
     // Buffers for writing register measurments to
-    // Some registers are 2 bytes, some are 3 bytes, the accumilation registers are 5 bytes
+    // Some registers are 2 bytes, some are 3 bytes, the accumulation registers are 5 bytes
     uint8_t buffer_2[2];
     uint8_t buffer_3[3];
     uint8_t buffer_5[5];
 
-    // For some of the registers the 4 least significant bits are reserved and always read zero, which is why we shift right 12, 4, then left 4 for vshunt, vbus and current
+    // For the vshunt, vbus and current registers the 4 least significant bits are reserved and always read zero, so use variant of flatten macro to extract value
     i2c_write_blocking(i2c_default, I2C_ADDR, &VSHUNT_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_3, 3, false);
-    *vshunt = ((buffer_3[0] << 12) | (buffer_3[1] << 4) | (buffer_3[2] >> 4)) * VSHUNT_FACTOR;
+    *vshunt = FLATTEN3_RESERVED(buffer_3) * VSHUNT_FACTOR;
 
     i2c_write_blocking(i2c_default, I2C_ADDR, &VBUS_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_3, 3, false);
-    *vbus = ((buffer_3[0] << 12) | (buffer_3[1] << 4) | (buffer_3[2] >> 4)) * VBUS_FACTOR;
+    *vbus = FLATTEN3_RESERVED(buffer_3) * VBUS_FACTOR;
 
     i2c_write_blocking(i2c_default, I2C_ADDR, &DIETEMP_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_2, 2, false);
-    *dietemp = ((buffer_2[0] << 8) + buffer_2[1]) * DIETEMP_FACTOR;
+    *dietemp = FLATTEN2(buffer_2) * DIETEMP_FACTOR;
 
     i2c_write_blocking(i2c_default, I2C_ADDR, &CURRENT_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_3, 3, false);
-    *current = ((buffer_3[0] << 12) | (buffer_3[1] << 4) | (buffer_3[2] >> 4)) * CURRENT_FACTOR;
+    *current = FLATTEN3_RESERVED(buffer_3) * CURRENT_FACTOR;
 
     i2c_write_blocking(i2c_default, I2C_ADDR, &POWER_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_3, 3, false);
-    *power = ((buffer_3[0] << 16) | (buffer_3[1] << 8) | buffer_3[2]) * POWER_FACTOR;
+    *power = FLATTEN3(buffer_3) * POWER_FACTOR;
 
     i2c_write_blocking(i2c_default, I2C_ADDR, &ENERGY_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_5, 5, false);
-    *energy = (((uint64_t) buffer_5[0] << 32) | (buffer_5[1] << 24) | (buffer_5[2] << 16) | (buffer_5[3] << 8) | buffer_5[4]) * ENERGY_FACTOR;
+    *energy = FLATTEN5(buffer_5) * ENERGY_FACTOR;
 
     i2c_write_blocking(i2c_default, I2C_ADDR, &CHARGE_REG, 1, true);
     i2c_read_blocking(i2c_default, I2C_ADDR, buffer_5, 5, false);
-    *charge = (((uint64_t) buffer_5[0] << 32) | (buffer_5[1] << 24) | (buffer_5[2] << 16) | (buffer_5[3] << 8) | buffer_5[4]) * CHARGE_FACTOR;
+    *charge = FLATTEN5(buffer_5) * CHARGE_FACTOR;
 }
 
 int main()
@@ -113,7 +119,7 @@ int main()
 
     while (true) {
         ina228_read(&vshunt, &vbus, &dietemp, &current, &power, &energy, &charge);
-        printf("INA228 Measurments:\nVSHUNT: %f\nVBUS: %f\nDIETEMP: %f\nCURRENT: %f\nPOWER: %f\nENERGY: %.9f\nCHARGE: %.9f\n-----------------\n", vshunt, vbus, dietemp, current, power, energy, charge);
-        sleep_ms(3000);
+        printf("INA228 Measurments:\nVSHUNT: %f V\nVBUS: %f V\nDIETEMP: %f °C\nCURRENT: %f A\nPOWER: %f W\nENERGY: %f J\nCHARGE: %f C\n-----------------\n", vshunt, vbus, dietemp, current, power, energy, charge);
+        sleep_ms(1000);
     }
 }