Fix bugs in AD57X4 driver implemenation

midi2cv/drivers/ad57x4.cc

@@ -1,8 +1,8 @@
 #include "ad57x4.h"
 #include "peripherals.h"
 #include "spi_mode.h"
-#include <stm32f3xx_hal.h>
 #include <math.h>
+#include <stm32f3xx_hal.h>
 
 static const uint32_t kPinEnable = GPIO_PIN_5;
 
@@ -16,26 +16,34 @@ void AD57X4::Init()
   HAL_GPIO_Init(GPIOB, &init);
 
   HAL_GPIO_WritePin(GPIOB, kPinEnable, GPIO_PIN_SET);
+
+  this->Write(REGISTER_CONTROL, 1, 0b100);
 }
 
-void AD57X4::WriteVoltage(uint8_t dac, float voltage) {
+void AD57X4::WriteVoltage(uint8_t dac, float voltage)
+{
+  CONSTRAIN(voltage, -10.799f, 10.799f);
   VoltageRange range = VOLTAGE_RANGE_FIVE_VOLTS;
-  if(fabs(voltage) > 5) range = VOLTAGE_RANGE_TEN_VOLTS;
+  if (fabs(voltage) > 5)
-  if(fabs(voltage) > 10) range = VOLTAGE_RANGE_TEN_EIGHT_VOLTS;
+    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_VOLTS)
-  if(range == VOLTAGE_RANGE_TEN_EIGHT_VOLTS) multiplier = 4.32f;
+    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);
+    int16_t value = (32768.0f * voltage) / (multiplier * refin);
 
     this->WriteDacBipolar(dac, range, value);
   } else {
     // convert to unsigned value
-    uint16_t value = (voltage / (multiplier * refin)) * (65535.0f);
+    uint16_t value = (65536.0f * voltage) / (multiplier * refin);
 
     this->WriteDacUnipolar(dac, range, value);
   }
@@ -47,17 +55,25 @@ void AD57X4::EnableAndSetRange(uint8_t dac, VoltageRange range, bool bipolar)
     // power on dac
     this->dacPower |= 1 << dac;
     this->Write(REGISTER_POWER_CONTROL, 0, this->dacPower);
+    for (int i = 0; i < 10000; i++)
+      asm("nop");
   }
-  if (this->dacRange[dac] != range) {
+  if (this->dacRange[dac] != range || this->dacBipolar[dac] != bipolar) {
     this->Write(REGISTER_OUTPUT_RANGE, dac, range + (bipolar ? 3 : 0));
     this->dacRange[dac] = range;
+    this->dacBipolar[dac] = bipolar;
   }
 }
 
+void AD57X4::WriteDac(uint8_t dac, VoltageRange range, uint16_t value, bool bipolar) {
+  EnableAndSetRange(dac, range, bipolar);
+  this->Write(REGISTER_DAC, dac, value);
+  this->Write(REGISTER_CONTROL, 0b101, 0); // LOAD command in Control Register
+}
+
 void AD57X4::WriteDacUnipolar(uint8_t dac, VoltageRange range, uint16_t value)
 {
-  EnableAndSetRange(dac, range, false);
+  WriteDac(dac, range, value, false);
-  this->Write(REGISTER_DAC, dac, value);
 }
 
 void AD57X4::WriteDacBipolar(uint8_t dac, VoltageRange range, int16_t value)
@@ -66,9 +82,7 @@ void AD57X4::WriteDacBipolar(uint8_t dac, VoltageRange range, int16_t value)
   if (value < 0) {
     twosComplement = ~(-value) + 1;
   }
-
+  WriteDac(dac, range, twosComplement, true);
-  EnableAndSetRange(dac, range, true);
-  this->Write(REGISTER_DAC, dac, twosComplement);
 }
 
 void AD57X4::Write(Register reg, uint8_t address, uint16_t data)
@@ -82,6 +96,7 @@ void AD57X4::Write(Register reg, uint8_t address, uint16_t data)
 
   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_SPI_Transmit(&hspi2, reinterpret_cast<uint8_t*>(&data) + 1, 1, HAL_MAX_DELAY);
+  HAL_SPI_Transmit(&hspi2, reinterpret_cast<uint8_t*>(&data), 1, HAL_MAX_DELAY);
   HAL_GPIO_WritePin(GPIOB, kPinEnable, GPIO_PIN_SET);
 }

midi2cv/drivers/ad57x4.h

@@ -12,8 +12,8 @@ enum VoltageRange {
 enum Register {
   REGISTER_DAC = 0,
   REGISTER_OUTPUT_RANGE = 1,
-  REGISTER_CONTROL = 2,
+  REGISTER_CONTROL = 3,
-  REGISTER_POWER_CONTROL = 3
+  REGISTER_POWER_CONTROL = 2
 };
 
 class AD57X4 {
@@ -34,6 +34,8 @@ class AD57X4 {
   private:
   uint8_t dacPower = 0;
   VoltageRange dacRange[4];
+  bool dacBipolar[4];
+  void WriteDac(uint8_t dac, VoltageRange range, uint16_t value, bool bipolar);
   void EnableAndSetRange(uint8_t dac, VoltageRange range, bool bipolar);
   void Write(Register reg, uint8_t address, uint16_t data);
   DISALLOW_COPY_AND_ASSIGN(AD57X4);

midi2cv/drivers/spi_mode.cc

@@ -45,7 +45,7 @@ void InitSPIAD5754(void)
   hspi2.Init.Direction = SPI_DIRECTION_2LINES;
   hspi2.Init.Mode = SPI_MODE_MASTER;
   hspi2.Init.DataSize = SPI_DATASIZE_8BIT;
-  hspi2.Init.CLKPolarity = SPI_POLARITY_LOW;
+  hspi2.Init.CLKPolarity = SPI_POLARITY_HIGH;
   hspi2.Init.CLKPhase = SPI_PHASE_1EDGE;
   hspi2.Init.NSS = SPI_NSS_SOFT;
   hspi2.Init.BaudRatePrescaler = SPI_BAUDRATEPRESCALER_2;

midi2cv/midi2cv.cc

@@ -112,7 +112,7 @@ void SysTick_Handler(void)
   system_clock.Tick();
 }
 
-void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef* htim)
+void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef* htim) // called with 1kHz (OPTIMIZE!) the display should get its own spi bus
 {
   if (htim != &htim2) {
     return;
@@ -120,12 +120,19 @@ void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef* htim)
 
   static uint16_t count = 0;
   count++;
-  if (count % (8000L / 20) == 0) {
+  if (count % (1000L / 20) == 0) {
     // refresh display with 20fps
     ui.Flush();
     count = 0;
   }
 
+  static float v = 0;
+  dac1.WriteVoltage(0, v+= 0.1f);
+  dac1.WriteVoltage(1, v*3);
+  dac1.WriteVoltage(2, v*5);
+  dac1.WriteVoltage(3, v*10);
+  if(v > 1) v = -1;
+
   // write audiodac1
   // write audiodac2
   // write audiodac3
@@ -136,7 +143,7 @@ void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef* htim)
 void InitTimers(void)
 {
   __HAL_RCC_TIM2_CLK_ENABLE();
-  htim2.Init.Period = F_CPU / (8000 * 1) - 1;
+  htim2.Init.Period = F_CPU / (1000 * 1) - 1;
   htim2.Init.Prescaler = 0;
   htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
   htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
@@ -161,6 +168,7 @@ void Init(void)
   //IWDG_Enable();
   display.Init();
   encoder.Init();
+  dac1.Init();
   InitTimers();
 }