eurorack/midi2cv/drivers/ad57x4.cc

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#include "ad57x4.h"
#include "peripherals.h"
#include "spi_mode.h"
#include <stm32f3xx_hal.h>
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#include <math.h>
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static const uint32_t kPinEnable = GPIO_PIN_5;
void AD57X4::Init()
{
GPIO_InitTypeDef init;
init.Pin = kPinEnable;
init.Mode = GPIO_MODE_OUTPUT_PP;
init.Pull = GPIO_NOPULL;
init.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOB, &init);
HAL_GPIO_WritePin(GPIOB, kPinEnable, GPIO_PIN_SET);
}
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void AD57X4::WriteVoltage(uint8_t dac, float voltage) {
VoltageRange range = VOLTAGE_RANGE_FIVE_VOLTS;
if(fabs(voltage) > 5) range = VOLTAGE_RANGE_TEN_VOLTS;
if(fabs(voltage) > 10) range = VOLTAGE_RANGE_TEN_EIGHT_VOLTS;
float multiplier = 2.0f;
if(range == VOLTAGE_RANGE_TEN_VOLTS) multiplier = 4.0f;
if(range == VOLTAGE_RANGE_TEN_EIGHT_VOLTS) multiplier = 4.32f;
float refin = 2.5f;
if(voltage < 0) {
// convert to signed value
int16_t value = (voltage / (multiplier * refin)) * (65535.0f);
this->WriteDacBipolar(dac, range, value);
} else {
// convert to unsigned value
uint16_t value = (voltage / (multiplier * refin)) * (65535.0f);
this->WriteDacUnipolar(dac, range, value);
}
}
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void AD57X4::EnableAndSetRange(uint8_t dac, VoltageRange range, bool bipolar)
{
if (!(this->dacPower & (1 << dac))) {
// power on dac
this->dacPower |= 1 << dac;
this->Write(REGISTER_POWER_CONTROL, 0, this->dacPower);
}
if (this->dacRange[dac] != range) {
this->Write(REGISTER_OUTPUT_RANGE, dac, range + (bipolar ? 3 : 0));
this->dacRange[dac] = range;
}
}
void AD57X4::WriteDacUnipolar(uint8_t dac, VoltageRange range, uint16_t value)
{
EnableAndSetRange(dac, range, false);
this->Write(REGISTER_DAC, dac, value);
}
void AD57X4::WriteDacBipolar(uint8_t dac, VoltageRange range, int16_t value)
{
uint16_t twosComplement = value;
if (value < 0) {
twosComplement = ~(-value) + 1;
}
EnableAndSetRange(dac, range, true);
this->Write(REGISTER_DAC, dac, twosComplement);
}
void AD57X4::Write(Register reg, uint8_t address, uint16_t data)
{
uint8_t first = address; // select address
first |= reg << 3; // select register
first |= 0 << 7; // write command
first |= 0 << 6; // always 0
InitSPI(SPI_MODE_DAC1);
HAL_GPIO_WritePin(GPIOB, kPinEnable, GPIO_PIN_RESET);
HAL_SPI_Transmit(&hspi2, &first, 1, HAL_MAX_DELAY); // write data
HAL_SPI_Transmit(&hspi2, reinterpret_cast<uint8_t*>(&data), 2, HAL_MAX_DELAY);
HAL_GPIO_WritePin(GPIOB, kPinEnable, GPIO_PIN_SET);
}