/***************************************************************************//**
* @brief Sets the output current of a channel.
*
* @param dev - The device structure.
* @param channel - Channel option.
* Example: AD5755_DAC_A
* AD5755_DAC_B
* AD5755_DAC_C
* AD5755_DAC_D
* @param m_acurrent - Value to be outputted by the DAC(milliampere).
*
* @return The actual current value that can be outputted by the channel.
*******************************************************************************/
float ad5755_set_current(struct ad5755_dev *dev,
uint8_t channel,
float m_acurrent)
{
int32_t offset = 0;
int32_t gain = 0;
int32_t range = 0;
int32_t dac_val = 0;
int32_t code = 0;
int8_t range_offset = 0;
float i_ref = 0;
float real_current = 0;
/* Get the offset, gain and range of the selected channel. */
offset = ad5755_get_register_value(dev,
AD5755_RD_OFFSET_REG(channel));
gain = ad5755_get_register_value(dev,
AD5755_RD_GAIN_REG(channel));
range = ad5755_get_register_value(dev,
AD5755_RD_CTRL_REG(channel)) & 0x7;
switch(range) {
case AD5755_R_4_20_MA : {
i_ref = 16.0; // mA
range_offset = 4; // mA
break;
}
case AD5755_R_0_20_MA : {
i_ref = 20.0; // mA
range_offset = 0; // mA
break;
}
case AD5755_R_0_24_MA : {
i_ref = 24.0; // mA
range_offset = 0; // mA
break;
}
default : {
i_ref = 1;
range_offset = 0;
break;
}
}
/* Compute the binary code from the value(mA) provided by user. */
code = (int32_t)((m_acurrent - range_offset) * (1l << 16) / i_ref);
if(code > 0xFFFF) {
code = 0xFFFF;
}
/* Offset and Gain are used to obtain the correct value to be written to the
DAC register in order to output the current desired by the user. */
if((code + (1l << 15) - offset) > 0) { // Avoid negative values
dac_val = (code + (1l << 15) - offset) * (1l << 16) / (gain + 1);
} else {
dac_val = 0;
}
/* Write to the Data Register of the DAC. */
ad5755_set_register_value(dev,
AD5755_DREG_WR_DAC,
channel,
dac_val);
real_current = (code * i_ref / (float)(1l << 16)) + range_offset;
return real_current;
}
/***************************************************************************//**
* @brief Sets the output current of a channel.
*
* @param channel - Channel option.
* Example: AD5755_DAC_A
* AD5755_DAC_B
* AD5755_DAC_C
* AD5755_DAC_D
* @param mACurrent - Value to be outputted by the DAC(milliampere).
*
* @return The actual current value that can be outputted by the channel.
*******************************************************************************/
float AD5755_SetCurrent(unsigned char channel, float mACurrent)
{
long offset = 0;
long gain = 0;
long range = 0;
long dacVal = 0;
long code = 0;
char rangeOffset = 0;
float iRef = 0;
float realCurrent = 0;
/* Get the offset, gain and range of the selected channel. */
offset = AD5755_GetRegisterValue(AD5755_RD_OFFSET_REG(channel));
gain = AD5755_GetRegisterValue(AD5755_RD_GAIN_REG(channel));
range = AD5755_GetRegisterValue(AD5755_RD_CTRL_REG(channel)) & 0x7;
switch(range)
{
case AD5755_R_4_20_MA :
{
iRef = 16.0; // mA
rangeOffset = 4; // mA
break;
}
case AD5755_R_0_20_MA :
{
iRef = 20.0; // mA
rangeOffset = 0; // mA
break;
}
case AD5755_R_0_24_MA :
{
iRef = 24.0; // mA
rangeOffset = 0; // mA
break;
}
default :
{
iRef = 1;
rangeOffset = 0;
break;
}
}
/* Compute the binary code from the value(mA) provided by user. */
code = (long)((mACurrent - rangeOffset) * (1l << 16) / iRef);
if(code > 0xFFFF)
{
code = 0xFFFF;
}
/* Offset and Gain are used to obtain the correct value to be written to the
DAC register in order to output the current desired by the user. */
if((code + (1l << 15) - offset) > 0) // Avoid negative values
{
dacVal = (code + (1l << 15) - offset) * (1l << 16) / (gain + 1);
}
else
{
dacVal = 0;
}
/* Write to the Data Register of the DAC. */
AD5755_SetRegisterValue(AD5755_DREG_WR_DAC,
channel,
dacVal);
realCurrent = (code * iRef / (float)(1l << 16)) + rangeOffset;
return realCurrent;
}
/***************************************************************************//**
* @brief Sets the output voltage of a channel.
*
* @param dev - The device structure.
* @param channel - Channel option.
* Example: AD5755_DAC_A
* AD5755_DAC_B
* AD5755_DAC_C
* AD5755_DAC_D
* @param voltage - Value to be outputted by the DAC(Volts).
*
* @return The actual voltage value that can be outputted by the channel.
*******************************************************************************/
float ad5755_set_voltage(struct ad5755_dev *dev,
uint8_t channel,
float voltage)
{
uint32_t offset = 0;
uint32_t gain = 0;
uint32_t dac_val = 0;
int32_t code = 0;
uint8_t range = 0;
uint8_t resolution = 0;
uint32_t range_offset = 0;
float v_ref = 0;
float real_voltage = 0;
if((dev->this_device == ID_AD5755) || (dev->this_device == ID_AD5755_1)) {
/* Get the offset, gain and range of the selected channel. */
offset = ad5755_get_register_value(dev,
AD5755_RD_OFFSET_REG(channel));
gain = ad5755_get_register_value(dev,
AD5755_RD_GAIN_REG(channel));
range = ad5755_get_register_value(dev,
AD5755_RD_CTRL_REG(channel)) & 0x7;
switch(range) {
case AD5755_R_0_5_V : {
range_offset = 0;
v_ref = 5.0;
resolution = 16;
break;
}
case AD5755_R_0_10_V : {
range_offset = 0;
v_ref = 10.0;
resolution = 16;
break;
}
case AD5755_R_M5_P5_V : {
range_offset = 0x8000;
v_ref = 5.0;
resolution = 15;
break;
}
case AD5755_R_M10_P10_V : {
range_offset = 0x8000;
v_ref = 10.0;
resolution = 15;
break;
}
default : {
range_offset = 0;
v_ref = 0;
resolution = 0;
break;
}
}
/* Compute the binary code from the users voltage value. */
code = (int32_t)(voltage * (1l << resolution) / v_ref) + range_offset;
if(code > 0xFFFF) {
code = 0xFFFF;
}
/* Offset and Gain are used to obtain the correct value to be written
to the DAC register in order to output the voltage desired by the user.
*/
if((int32_t)(code + (1l << 15) - offset) > 0) { // Avoid negative values
dac_val = (code + (1l << 15) - offset) * (1l << 16) / (gain + 1);
} else {
dac_val = 0;
}
/* Write to the Data Register of the DAC. */
ad5755_set_register_value(dev,
AD5755_DREG_WR_DAC,
channel,
dac_val);
real_voltage = ((int32_t)(dac_val - range_offset) * v_ref) /
(1l << resolution);
}
return real_voltage;
}
/***************************************************************************//**
* @brief Sets the output voltage of a channel.
*
* @param channel - Channel option.
* Example: AD5755_DAC_A
* AD5755_DAC_B
* AD5755_DAC_C
* AD5755_DAC_D
* @param voltage - Value to be outputted by the DAC(Volts).
*
* @return The actual voltage value that can be outputted by the channel.
*******************************************************************************/
float AD5755_SetVoltage(unsigned char channel, float voltage)
{
unsigned long offset = 0;
unsigned long gain = 0;
unsigned long dacVal = 0;
unsigned long code = 0;
unsigned char range = 0;
unsigned char resolution = 0;
unsigned long rangeOffset = 0;
float vRef = 0;
float realVoltage = 0;
if((this_device == ID_AD5755) || (this_device == ID_AD5755_1))
{
/* Get the offset, gain and range of the selected channel. */
offset = AD5755_GetRegisterValue(AD5755_RD_OFFSET_REG(channel));
gain = AD5755_GetRegisterValue(AD5755_RD_GAIN_REG(channel));
range = AD5755_GetRegisterValue(AD5755_RD_CTRL_REG(channel)) & 0x7;
switch(range)
{
case AD5755_R_0_5_V :
{
rangeOffset = 0;
vRef = 5.0;
resolution = 16;
break;
}
case AD5755_R_0_10_V :
{
rangeOffset = 0;
vRef = 10.0;
resolution = 16;
break;
}
case AD5755_R_M5_P5_V :
{
rangeOffset = 0x8000;
vRef = 5.0;
resolution = 15;
break;
}
case AD5755_R_M10_P10_V :
{
rangeOffset = 0x8000;
vRef = 10.0;
resolution = 15;
break;
}
default :
{
rangeOffset = 0;
vRef = 0;
resolution = 0;
break;
}
}
/* Compute the binary code from the users voltage value. */
code = (long)(voltage * (1l << resolution) / vRef) + rangeOffset;
if(code > 0xFFFF)
{
code = 0xFFFF;
}
/* Offset and Gain are used to obtain the correct value to be written
to the DAC register in order to output the voltage desired by the user.
*/
if((code + (1l << 15) - offset) > 0) // Avoid negative values
{
dacVal = (code + (1l << 15) - offset) * (1l << 16) / (gain + 1);
}
else
{
dacVal = 0;
}
/* Write to the Data Register of the DAC. */
AD5755_SetRegisterValue(AD5755_DREG_WR_DAC,
channel,
dacVal);
realVoltage = ((long)(code - rangeOffset) * vRef) / (1l << resolution);
}
return realVoltage;
}