Added doxygen comments and refactored a few functions

riscv-bldc-forced-commutation/src/riscv-bldc.cpp

@@ -16,14 +16,15 @@
 
 #include "hifive1_io.h"
 
-volatile uint32_t nextCommutationStep;
+volatile uint32_t nextCommutationStep=0;
-/*
+
-Kommutierungsblöcke
+/* commutation blocks
-    1   2   3   4   5   6
+ *     1   2   3   4   5   6
-U   0   z   +1  +1  z   0
+ * U   0   z   +1  +1  z   0
-V   +1  +1  z   0   0   z
+ * V   +1  +1  z   0   0   z
-W   z   0   0   z   +1  +1
+ * W   z   0   0   z   +1  +1
-*/
+ */
+
 std::array<uint32_t, 6> driveTable { //! Drive pattern for commutation, CW rotation
             ((1 << VH) | (1 << UL)), //1
             ((1 << VH) | (1 << WL)), //2
@@ -32,6 +33,7 @@ std::array<uint32_t, 6> driveTable { //! Drive pattern for commutation, CW rotat
             ((1 << WH) | (1 << VL)), //5
             ((1 << WH) | (1 << UL))  //6
 };
+
 std::array<uint32_t, 6> senseTable { //! channels to sense during the applied pattern
     SENSW_N, //1
     SENSU_P, //2
@@ -44,10 +46,14 @@ std::array<uint32_t, 6> senseTable { //! channels to sense during the applied pa
 bool ccw=false;
 
 typedef void (*function_ptr_t) (void);
-// Instance data for the PLIC.
+//! Instance data for the PLIC.
 plic_instance_t g_plic;
 std::array<function_ptr_t,PLIC_NUM_INTERRUPTS>  g_ext_interrupt_handlers;
-
+/*! \brief external interrupt handler
+ *
+ * routes the peripheral interrupts to the the respective handler
+ *
+ */
 extern "C" void handle_m_ext_interrupt() {
     plic_source int_num  = PLIC_claim_interrupt(&g_plic);
     if ((int_num >=1 ) && (int_num < PLIC_NUM_INTERRUPTS))
@@ -56,8 +62,9 @@ extern "C" void handle_m_ext_interrupt() {
       exit(1 + (uintptr_t) int_num);
     PLIC_complete_interrupt(&g_plic, int_num);
 }
-
+/*! \brief  mtime interval interrupt
-// 1sec interval interrupt
+ *
+ */
 extern "C" void handle_m_time_interrupt(){
     clear_csr(mie, MIP_MTIP);
     // Reset the timer for 3s in the future.
@@ -70,9 +77,13 @@ extern "C" void handle_m_time_interrupt(){
     // Re-enable the timer interrupt.
     set_csr(mie, MIP_MTIP);
 }
-
+/*! \brief dummy interrupt handler
+ *
+ */
 void no_interrupt_handler (void) {};
-
+/*! \brief configure the per-interrupt handler
+ *
+ */
 void configure_irq(size_t irq_num, function_ptr_t handler, unsigned char prio=1) {
     g_ext_interrupt_handlers[irq_num] = handler;
     // Priority must be set > 0 to trigger the interrupt.
@@ -80,7 +91,9 @@ void configure_irq(size_t irq_num, function_ptr_t handler, unsigned char prio=1)
     // Have to enable the interrupt both at the GPIO level, and at the PLIC level.
     PLIC_enable_interrupt(&g_plic, irq_num);
 }
-
+/*!\brief initializes platform
+ *
+ */
 void platform_init(){
     // configure clocks
     PRCI_use_hfxosc(1); // is equivalent to
@@ -125,7 +138,9 @@ void platform_init(){
     // Enable interrupts in general.
     set_csr(mstatus, MSTATUS_MIE);
 }
-
+/*! \brief reads adc channel and returns measured value
+ *
+ */
 unsigned read_adc(unsigned channel){
     std::array<uint8_t, 3> bytes{
                 uint8_t(0x06 | (channel>>2 & 0x1)), /* start bit, single ended measurement, channel[2] */
@@ -137,13 +152,8 @@ unsigned read_adc(unsigned channel){
     qspi1::transfer(bytes);
     return (bytes[1]&0xf)*256+bytes[2];
 }
-
+/*! \brief waits for zero crossing and measures time until
-/*! \brief Generates a delay used during startup
  *
- *  This functions is used to generate a delay during the startup procedure.
- *  The length of the delay equals delay * STARTUP_DELAY_MULTIPLIER microseconds.
- *  Since Timer/Counter1 is used in this function, it must never be called when
- *  sensorless operation is running.
  */
 unsigned short measured_zc_time(unsigned short max_delay){
     long delay_us = max_delay;
@@ -169,21 +179,25 @@ unsigned short measured_zc_time(unsigned short max_delay){
     pwm0::cfg_reg().enoneshot=false;
     return sreg*(1<<scaling_factor);
 }
-
+/*! \brief calculates the next commutation step
-void next_commutation_step(void) {
+ *
+ */
+inline void next_commutation_step(void) {
     if (ccw) {
-        if (nextCommutationStep == 0)
+        nextCommutationStep = nextCommutationStep == 0? 5 : nextCommutationStep-1;
-            nextCommutationStep = 0;
-        else
-            nextCommutationStep--;
     } else {
-        if (nextCommutationStep == 5)
+        nextCommutationStep = nextCommutationStep == 5? 0 : nextCommutationStep+1;
-            nextCommutationStep = 0;
-        else
-            nextCommutationStep++;
     }
 }
-
+/*! \brief write the drive pattern to gpio
+ *
+ */
+void setDrivePattern(uint32_t nextDrivePattern) {
+    gpio0::port_reg() = (gpio0::port_reg() & ~DRIVE_MASK & 0x00ffffff) | nextDrivePattern | nextCommutationStep << 24;
+}
+/*! \brief open-loop commutation to start the motor
+ *
+ */
 void start_open_loop(void){
     auto delay = 30120U;
     std::array<double, 2> multiplier={0.83, 1.0};
@@ -195,8 +209,7 @@ void start_open_loop(void){
     next_commutation_step();
     auto nextDrivePattern = driveTable[nextCommutationStep];
     for (size_t i = 0; i < 12; i++){
-        gpio0::port_reg() = (gpio0::port_reg() & ~DRIVE_MASK & 0x00ffffff)
+        setDrivePattern(nextDrivePattern);
-                | nextDrivePattern | nextCommutationStep<<24;
         auto channel=senseTable[nextCommutationStep]&0x3;
         auto zcPolRise = senseTable[nextCommutationStep]<4;
         auto bemf_0=read_adc(channel);
@@ -208,21 +221,24 @@ void start_open_loop(void){
         nextDrivePattern = driveTable[nextCommutationStep];
     }
 }
-
+/*! \brief closed-loop commutation to run the motor
+ *
+ */
 void run_closed_loop(void){
     auto count=0;
     auto zc_delay=0U;
     auto tmp=0U;
     auto nextDrivePattern = driveTable[nextCommutationStep];
     for(;;){
-        gpio0::port_reg() = (gpio0::port_reg() & ~DRIVE_MASK & 0x00ffffff)
+        setDrivePattern(nextDrivePattern);
-                | nextDrivePattern | nextCommutationStep<<24;
         zc_delay=measured_zc_time(50000);
         next_commutation_step();
         nextDrivePattern = driveTable[nextCommutationStep];
     }
 }
-
+/*! \brief main function
+ *
+ */
 int main() {
     platform_init();
     printf("Starting motor\n");