Support configuration of microstepping behaviour

.gitignore

@@ -1,3 +1,6 @@
 .pioenvs
 .piolibdeps
 ardufocus/localcfg.h
+.vscode
+.pio
+workspace.code-workspace

ardufocus/a4988.cpp

@@ -20,8 +20,9 @@
 #include "a4988.h"
 
 /**
- * @brief [brief description]
- * @details [long description]
+ * @brief Initialize Arduino pins for A4988 step stick according to pinout in config.h
+ * @details Configure Arduino pins, so we are able to drive the stepper motor. 
+ * This routine sets the step resolution.  
  *
  */
 void a4988::init()
@@ -35,9 +36,11 @@ void a4988::init()
   IO::set_as_output(m_pinout.sleep);
   IO::set_as_output(m_pinout.direction);
 
-  IO::write(m_pinout.ms1,        LOW);
-  IO::write(m_pinout.ms2,        LOW);
-  IO::write(m_pinout.ms3,        LOW);
+  // Step resolution: Sixteenth step
+  IO::write(m_pinout.ms1,        HIGH);
+  IO::write(m_pinout.ms2,        HIGH);
+  IO::write(m_pinout.ms3,        HIGH);
+
   IO::write(m_pinout.step,       LOW);
   IO::write(m_pinout.direction,  LOW);
 
@@ -64,13 +67,13 @@ void a4988::halt()
 
 
 /**
- * @brief [brief description]
- * @details [long description]
+ * @brief Set microstepping resolution: Full step
+ * @details Use the microstepping resolution pins to configure a "full step" per pulse.
  *
  */
 void a4988::set_full_step()
 {
-  m_mode = 0x00;
+  m_mode = 1;
   IO::write(m_pinout.ms1, LOW);
   IO::write(m_pinout.ms2, LOW);
   IO::write(m_pinout.ms3, LOW);
@@ -81,13 +84,13 @@ void a4988::set_full_step()
 
 
 /**
- * @brief [brief description]
- * @details [long description]
+ * @brief Set microstepping resolution: half step
+ * @details Use the microstepping resolutions pins to configure a "half step" per pulse resolution.
  *
  */
 void a4988::set_half_step()
 {
-  m_mode = 0xFF;
+  m_mode = 2;
   IO::write(m_pinout.ms1, HIGH);
   IO::write(m_pinout.ms2, LOW);
   IO::write(m_pinout.ms3, LOW);
@@ -96,6 +99,56 @@ void a4988::set_half_step()
   util::delay_2us();
 }
 
+/**
+ * @brief Set microstepping resolution: half step
+ * @details Use the microstepping resolutions pins to configure a "half step" per pulse resolution.
+ *
+ */
+void a4988::set_quarter_step()
+{
+  m_mode = 4;
+  IO::write(m_pinout.ms1, LOW);
+  IO::write(m_pinout.ms2, HIGH);
+  IO::write(m_pinout.ms3, LOW);
+
+  // A4988: 400ns, A8825: 1.3us
+  util::delay_2us();
+}
+
+/**
+ * @brief Set microstepping resolution: half step
+ * @details Use the microstepping resolutions pins to configure a "half step" per pulse resolution.
+ *
+ */
+void a4988::set_eighth_step()
+{
+  m_mode = 8;
+  IO::write(m_pinout.ms1, HIGH);
+  IO::write(m_pinout.ms2, HIGH);
+  IO::write(m_pinout.ms3, LOW);
+
+  // A4988: 400ns, A8825: 1.3us
+  util::delay_2us();
+}
+
+/**
+ * @brief Set microstepping resolution: half step
+ * @details Use the microstepping resolutions pins to configure a "half step" per pulse resolution.
+ *
+ */
+void a4988::set_sixteenth_step()
+{
+  m_mode = 16;
+  IO::write(m_pinout.ms1, HIGH);
+  IO::write(m_pinout.ms2, HIGH);
+  IO::write(m_pinout.ms3, HIGH);
+
+  // A4988: 400ns, A8825: 1.3us
+  util::delay_2us();
+}
+
+// Disable 'implicit fall-through' warning, as the switch statements fall-through on purpose.
+#pragma GCC diagnostic ignored "-Wimplicit-fallthrough="
 
 /**
  * @brief [brief description]
@@ -141,11 +194,13 @@ bool a4988::step_ccw()
       return step();
   }
 }
+// Restore warnings to command line parameters.
+#pragma GCC diagnostic pop
 
 
 /**
- * @brief [brief description]
- * @details [long description]
+ * @brief Move the stepper motor one step.
+ * @details Writes a pulse on the output pin, to advance the motor according to the set resolution.
  *
  */
 bool a4988::step()

ardufocus/a4988.h

@@ -50,6 +50,14 @@ class a4988: public stepper
      *  DIR |o      ---  o| GND
      *       `-----------´
      *
+     * Pin description according to A4988 data sheet, e.g. https://pdf1.alldatasheet.com/datasheet-pdf/view/338780/ALLEGRO/A4988.html
+     * 
+     * ENA: Enable (negated logic)
+     * RST: Reset (negated logic)
+     * SLP: Sleep (negated logic)
+     * MS1,MS2,MS3: Microstepping resolution, LLL = full step, HLL = half step, LHL = quarter, HHL = eighth, HHH = 1/16th step.
+     * DIR: Direction
+     * STP: Step
      */
 
   protected:
@@ -64,6 +72,9 @@ class a4988: public stepper
     virtual void sleep();
     virtual void set_full_step();
     virtual void set_half_step();
+    virtual void set_quarter_step();
+    virtual void set_eighth_step();
+    virtual void set_sixteenth_step();
     virtual speed bool step_cw();
     virtual speed bool step_ccw();
 

ardufocus/api.h

@@ -211,13 +211,31 @@ class api {
       switch(idx) {
         case MOTOR_ONE:
           #ifdef MOTOR1_HAS_DRIVER
-          g_motor1->set_full_step();
+          g_motor1->set_step_mode(0);
+          // We rely on the compiler to optimize away the ifs, where the condition is false.
+          if (STEPPER_FULLSTEP_MICRORES == 1) 
+            g_motor1->set_full_step();
+          if (STEPPER_FULLSTEP_MICRORES == 2)
+            g_motor1->set_half_step();
+          if (STEPPER_FULLSTEP_MICRORES == 4)
+            g_motor1->set_quarter_step();
+          if (STEPPER_FULLSTEP_MICRORES == 8)
+            g_motor1->set_eighth_step();
           #endif
           break;
 
         case MOTOR_TWO:
           #ifdef MOTOR2_HAS_DRIVER
-          g_motor2->set_full_step();
+          g_motor2->set_step_mode(0);
+          // We rely on the compiler to optimize away the ifs, where the condition is false.
+          if (STEPPER_FULLSTEP_MICRORES == 1)
+            g_motor2->set_full_step();
+          if (STEPPER_FULLSTEP_MICRORES == 2)
+            g_motor2->set_half_step();
+          if (STEPPER_FULLSTEP_MICRORES == 4)
+            g_motor2->set_quarter_step();
+          if (STEPPER_FULLSTEP_MICRORES == 8)
+            g_motor2->set_eighth_step();
           #endif
           break;
 
@@ -230,13 +248,31 @@ class api {
       switch(idx) {
         case MOTOR_ONE:
           #ifdef MOTOR1_HAS_DRIVER
-          g_motor1->set_half_step();
+          g_motor1->set_step_mode(0xff);
+          // We rely on the compiler to optimize away the ifs, where the condition is false.
+          if (STEPPER_FULLSTEP_MICRORES == 1)
+            g_motor1->set_half_step();
+          if (STEPPER_FULLSTEP_MICRORES == 2)
+            g_motor1->set_quarter_step();
+          if (STEPPER_FULLSTEP_MICRORES == 4)
+            g_motor1->set_eighth_step();
+          if (STEPPER_FULLSTEP_MICRORES == 8)
+            g_motor1->set_sixteenth_step();  
           #endif
           break;
 
         case MOTOR_TWO:
           #ifdef MOTOR2_HAS_DRIVER
-          g_motor2->set_half_step();
+          g_motor2->set_step_mode(0xff);
+          // We rely on the compiler to optimize away the ifs, where the condition is false.
+          if (STEPPER_FULLSTEP_MICRORES == 1)
+            g_motor2->set_half_step();
+          if (STEPPER_FULLSTEP_MICRORES == 2)
+            g_motor2->set_quarter_step();
+          if (STEPPER_FULLSTEP_MICRORES == 4)
+            g_motor2->set_eighth_step();
+          if (STEPPER_FULLSTEP_MICRORES == 8)
+            g_motor2->set_sixteenth_step();  
           #endif
           break;
 

ardufocus/assert.h

@@ -213,6 +213,19 @@
     #endif
 #endif
 
+// Microstepping behaviour sanity checks
+#if !(STEPPER_FULLSTEP_MICRORES == 1 || STEPPER_FULLSTEP_MICRORES == 2 || STEPPER_FULLSTEP_MICRORES == 4 || STEPPER_FULLSTEP_MICRORES == 8)
+    #error The STEPPER_FULLSTEP_MICRORES must be 1,2,4 or 8. 
+#endif 
+
+#if (STEPPER_FULLSTEP_MICRORES > 1) && defined(MOTOR1_HAS_DRIVER) && !defined(MOTOR1_USE_A4988_DRIVER)
+    #error STEPPER_FULLSTEP_MICRORES > 1 is only supported by the A4988 driver. Check MOTOR1 driver.
+#endif
+
+#if (STEPPER_FULLSTEP_MICRORES > 1) && defined(MOTOR2_HAS_DRIVER) && !defined(MOTOR2_USE_A4988_DRIVER)
+    #error STEPPER_FULLSTEP_MICRORES > 1 is only supported by the A4988 driver. Check MOTOR2 driver.
+#endif 
+
 // USER INTERFACE: Keyboard ---------------------------------------------------
 #if defined(USE_UI_KAP)
   #if defined(UI_KAP_BUTTON_DEBOUNCE) && (UI_KAP_BUTTON_DEBOUNCE < 1 || UI_KAP_BUTTON_DEBOUNCE > 255)

ardufocus/config.h

@@ -136,7 +136,7 @@
 //  - Max speed: 1000
 //  - Min speed: 250
 //
-#define MOTOR1_MAX_SPEED 150
+#define MOTOR1_MAX_SPEED 250
 #define MOTOR1_MIN_SPEED  25
 
 
@@ -175,6 +175,19 @@
 // any acceleration control. The default value is 10 steps of left undefined.
 //#define ACCEL_MIN_STEPS 10
 
+// ----------------------------------------------------------------------------
+// Microstepping Resolution ---------------------------------------------------
+// ----------------------------------------------------------------------------
+// 
+// Moonlite protocol supports two differnt speed modes for controlling the focuser:
+// "Full step mode" and "half step mode". Here you can configure, which microstepping is 
+// considered a "full step". Allowed values are 1,2,4,8 for full steps, half steps, 
+// quarter steps or eighth steps respectively. Half mode is the next one.
+// (Note: At the moment this is a global setting for all stepper motors and 
+// is not supported by the ULN2003 driver, for which it must be one)
+#define STEPPER_FULLSTEP_MICRORES 8
+
+
 
 // ----------------------------------------------------------------------------
 // TEMPERATURE SENSOR ---------------------------------------------------------
@@ -204,10 +217,12 @@
 // This is the most basic user interface, it uses two keys to move the focuser
 // IN (FWD) and out (BWD). A third key (SWT) can be used to select the active
 // motor on a dual motor configuration.
-//#define USE_UI_KAP
+#define USE_UI_KAP
 
 // Use the following setings to select the input pins connected to each one of
 // the switches. The third button is optional.
+// 16 = A2 on Arduino Nano
+// 17 = A3 on Arduino Nano
 #define UI_KAP_FWD_BUTTON_PIN 16
 #define UI_KAP_BWD_BUTTON_PIN 17
 //#define UI_KAP_SWT_BUTTON_PIN 18
@@ -221,13 +236,14 @@
 //  GND --- | SWITCH | --- INPUT_PIN
 //           --------
 //
+// So, if you want to use active high logic on the input button switches, define this:
 //#define UI_KAP_INVERT_BUTTON_LOGIC
 
 // The options bellow allows you to have one LED per button, the LED will light
 // up when the button is pressed. The third button (SWT) will be lit when the
 // first motor is active, and off when the second motor is active.
-//#define UI_KAP_FWD_BUTTON_LED_PIN 13
-//#define UI_KAP_BWD_BUTTON_LED_PIN 13
+#define UI_KAP_FWD_BUTTON_LED_PIN 3
+#define UI_KAP_BWD_BUTTON_LED_PIN 4
 //#define UI_KAP_SWT_BUTTON_LED_PIN 13
 
 // Pin A0 is channel 0 (..) pin A3 is channel 3

ardufocus/stepper.h

@@ -76,7 +76,11 @@ class stepper
     virtual inline void sleep()                        { ; }
     virtual inline void set_full_step()                { ; }
     virtual inline void set_half_step()                { ; }
+    virtual inline void set_quarter_step()             { ; }
+    virtual inline void set_eighth_step()              { ; }
+    virtual inline void set_sixteenth_step()           { ; }
 
+    virtual inline void set_step_mode(uint8_t mode)    { m_mode = mode;             }
     virtual inline uint8_t get_step_mode()             { return m_mode;             }
 
     virtual inline bool step_cw()                      { return false;              }

ardufocus/uln2003.h

@@ -50,6 +50,10 @@ class uln2003: public stepper
     virtual void sleep();
     virtual void set_full_step();
     virtual void set_half_step();
+    // Not supported.
+    virtual inline void set_quarter_step()   { ; };
+    virtual inline void set_eighth_step()    { ; };
+    virtual inline void set_sixteenth_step() { ; };
     virtual speed bool step_cw();
     virtual speed bool step_ccw();
 

platformio.ini

@@ -68,7 +68,11 @@ src_build_flags = ${common.src_build_flags}
 lib_deps        = ${common.lib_deps_external}
 ; Uncomment this line if you have upgraded the bootloader
 ; on your Arduino Nano
-upload_speed    = 115200
+;upload_speed    = 115200
+monitor_flags = 
+  --echo
+monitor_filters = colorize, send_on_enter # , debug
+
 
 [env:nano328pb]
 platform        = atmelavr