new function set_offset_config

added new function for setting offset value for DC offset compensation

Author: Silver Kuusik

AD7173.cpp

@@ -96,8 +96,10 @@ int AD7173Class::get_current_data_channel(register_t &channel) {
 	/* get ADC status register */
 	byte value[1];
 	this->get_register(STATUS_REG, value, 1);
+
 	/* assign to return channel register value */
 	channel = (register_t) (value[0] & 0x0F);
+
 	/* return error code */
 	return 0;
 }
@@ -110,10 +112,10 @@ int AD7173Class::set_adc_mode_config(data_mode_t data_mode, clock_mode_t clock_m
 	byte value[2] = {0x00, 0x00};
 	value[1] = (data_mode << 4) | (clock_mode << 2);
 
-	/* update the desired adc_mode configuration */
+	/* update the configuration value */
 	this->set_register(ADCMODE_REG, value, 2);
 
-	/* verify updated adc_mode configuration */
+	/* verify the updated configuration value */
 	this->get_register(ADCMODE_REG, value, 2);
 
 	/* return error code */
@@ -128,10 +130,10 @@ int AD7173Class::set_interface_mode_config(bool continuous_read) {
 	byte value[2] = {0x00, 0x00};
 	value[1] = (continuous_read << 7);
 
-	/* update the desired interface_mode configuration */
+	/* update the configuration value */
 	this->set_register(IFMODE_REG, value, 2);
 
-	/* verify updated interface_mode configuration */
+	/* verify the updated configuration value */
 	this->get_register(IFMODE_REG, value, 2);
 
 	/* when continuous read mode */
@@ -207,10 +209,10 @@ int AD7173Class::set_channel_config(register_t channel, bool enable, register_t
 	value[0] = (enable << 7) | (setup << 4) | (ain_pos >> 3);
 	value[1] = (ain_pos << 5) | ain_neg;
 
-	/* update the desired channel configuration */
+	/* update the configuration value */
 	this->set_register(channel, value, 2);
 
-	/* verify the updated channel configuration */
+	/* verify the updated configuration value */
 	this->get_register(channel, value, 2);
 
 	/* return error code */
@@ -225,10 +227,10 @@ int AD7173Class::set_setup_config(register_t setup, coding_mode_t coding_mode) {
 	value[0] = (coding_mode << 4);
 	value[1] = 0x00;
 
-	/* update the desired setup configuration */
+	/* update the configuration value */
 	this->set_register(setup, value, 2);
 
-	/* verify the updated setup configuration */
+	/* verify the updated configuration value */
 	this->get_register(setup, value, 2);
 
 	/* return error code */
@@ -243,12 +245,31 @@ int AD7173Class::set_filter_config(register_t filter, data_rate_t data_rate) {
 	/* SINC3_MAP0 [15], RESERVED [14:12], ENHFILTEN0 [11], ENHFILT0 [10:8], RESERVED [7], ORDER0 [6:5], ORD0 [4:0] */
 	value[1] = data_rate;
 
-	/* update the desired filter configuration */
+	/* update the configuration value */
 	this->set_register(filter, value, 2);
 
-	/* verify updated filter configuration */
+	/* verify the updated configuration value */
 	this->get_register(filter, value, 2);
 
+	/* return error code */
+	return 0;
+}
+
+int AD7173Class::set_offset_config(register_t offset, uint32_t offset_value) {
+	/* Address Range: 0x30 to 0x37, Reset: 0x0000, Name: OFFSET0 to OFFSET7 */
+
+	/* prepare the configuration value */
+	byte value[3] = {0x00, 0x00, 0x00};
+	value[0] = offset_value;
+	value[1] = offset_value >> 8;
+	value[2] = offset_value >> 16;
+
+	/* update the configuration value */
+	this->set_register(offset, value, 3);
+
+	/* verify the updated configuration value */
+	this->get_register(offset, value, 3);
+
 	/* return error code */
 	return 0;
 }

AD7173.h

@@ -311,6 +311,16 @@ class AD7173Class {
 	*/
 	int set_filter_config(register_t, data_rate_t);
 
+	/*
+	======================================
+	sets the ADC offset compensation value
+	@param byte - offset register
+	@param uint32_t - offset value
+	@return int - error code
+	======================================
+	*/
+	int set_offset_config(register_t, uint32_t);
+
 private:
 	/* ADC data mode */
 	data_mode_t m_data_mode;

README.md

@@ -6,14 +6,14 @@ This library is developed for AD7173 to be used with Brain-Duino and therefore i
 For Brain-Duino we use the following setup, meaning this is the most tested setup for this library:
 
 * 1007 data rate
-* internal clock
+* external crystal
 * continuous conversion mode
 * 4 analog inputs, 2 bipolar channels
 
 ```c
-AD7173.set_clock_mode(INTERNAL_CLOCK);
-AD7173.set_data_rate(FILTER0, SPS_1007);
-AD7173.setup_channel(CH0, true, AIN8, AIN9);
-AD7173.setup_channel(CH1, true, AIN10, AIN11); 
-AD7173.set_data_mode(CONTINUOUS_CONVERSION_MODE);
+AD7173.set_channel_config(CH0, true, SETUP0, AIN8, AIN9);
+AD7173.set_channel_config(CH1, true, SETUP0, AIN10, AIN11);
+AD7173.set_setup_config(SETUP0, BIPOLAR);
+AD7173.set_filter_config(FILTER0, SPS_1007);
+AD7173.set_adc_mode_config(CONTINUOUS_CONVERSION_MODE, EXTERNAL_CRYSTAL);
 ```

examples/Basic/Basic.ino

@@ -19,9 +19,6 @@ void setup() {
 	/* reset the ADC registers to default */
 	AD7173.reset();
 
-	/* resync the ADC */
-	AD7173.sync();
-
 	/* check if the ID register of the ADC is valid */
 	if (AD7173.is_valid_id()) Serial.println("AD7173 ID is valid");
 	else Serial.println("AD7173 ID is invalid");
@@ -40,6 +37,10 @@ void setup() {
 	/* BIPOLAR, UNIPOLAR */
 	AD7173.set_setup_config(SETUP0, BIPOLAR);
 
+	/* set ADC OFFSET0 offset value */
+	/* OFFSET0 - OFFSET7 */
+	AD7173.set_offset_config(OFFSET0, 8388608);
+
 	/* set the ADC FILTER0 ac_rejection to false and samplingrate to 1007 Hz */
 	/* FILTER0 - FILTER7 */
 	/* SPS_1, SPS_2, SPS_5, SPS_10, SPS_16, SPS_20, SPS_49, SPS_59, SPS_100, SPS_200 */

keywords.txt

@@ -18,6 +18,7 @@ sync	KEYWORD2
 get_data	KEYWORD2
 is_valid_id	KEYWORD2
 set_setup_config	KEYWORD2
+set_offset_config	KEYWORD2
 set_filter_config	KEYWORD2
 set_channel_config	KEYWORD2
 set_adc_mode_config	KEYWORD2
@@ -104,6 +105,15 @@ SETUP5	LITERAL1
 SETUP6	LITERAL1
 SETUP7	LITERAL1
 
+OFFSET0	LITERAL1
+OFFSET1	LITERAL1
+OFFSET2	LITERAL1
+OFFSET3	LITERAL1
+OFFSET4	LITERAL1
+OFFSET5	LITERAL1
+OFFSET6	LITERAL1
+OFFSET7	LITERAL1
+
 DATA_READY	LITERAL1
 
 BIPOLAR	LITERAL1

library.properties

@@ -1,5 +1,5 @@
 name=AD7173
-version=0.2.1
+version=0.3
 author=Silver Kuusik <silver.kuusik@gmail.com>
 maintainer=Silver Kuusik <silver.kuusik@gmail.com>
 sentence=Arduino library for Analog Devices AD7173 analog digital converter