Fix INDEX_OF_AXIS

MarlinFirmware · Sep 23, 2021 · ea051e1 · ea051e1
1 parent b87ab9b
commit ea051e1
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Showing 2 changed files with 17 additions and 3 deletions.
diff --git a/Marlin/src/inc/Conditionals_LCD.h b/Marlin/src/inc/Conditionals_LCD.h
@@ -573,6 +573,8 @@
  *  HOTENDS      - Number of hotends, whether connected or separate
  *  E_STEPPERS   - Number of actual E stepper motors
  *  E_MANUAL     - Number of E steppers for LCD move options
+ *
+ * These defines must be simple constants for use in REPEAT, etc.
  */
 #if EXTRUDERS
   #define HAS_EXTRUDERS 1
@@ -602,7 +604,13 @@
 
 #elif ENABLED(SWITCHING_EXTRUDER)   // One stepper for every two EXTRUDERS
 
-  #define E_STEPPERS      ((EXTRUDERS + 1) / 2)
+  #if EXTRUDERS > 4
+    #define E_STEPPERS    3
+  #elif EXTRUDERS > 2
+    #define E_STEPPERS    2
+  #else
+    #define E_STEPPERS    1
+  #endif
   #if DISABLED(SWITCHING_NOZZLE)
     #define HOTENDS       E_STEPPERS
   #endif

diff --git a/Marlin/src/module/stepper.h b/Marlin/src/module/stepper.h
@@ -260,10 +260,16 @@ constexpr pin_t ena_pins[] = {
 };
 
 // Index of the axis or extruder element in a combined array
-constexpr int8_t index_of_axis(const AxisEnum axis E_OPTARG(const uint8_t eindex=0)) {
+constexpr uint8_t index_of_axis(const AxisEnum axis E_OPTARG(const uint8_t eindex=0)) {
   return uint8_t(axis) + (E_TERN0(axis < LINEAR_AXES ? 0 : eindex));
 }
-#define INDEX_OF_AXIS(A,V...) index_of_axis(A E_OPTARG(#V))
+//#define __IAX_N(N,V...)           _IAX_##N(V)
+//#define _IAX_N(N,V...)            __IAX_N(N,V)
+//#define _IAX_1(A)                 index_of_axis(A)
+//#define _IAX_2(A,B)               index_of_axis(A E_OPTARG(B))
+//#define INDEX_OF_AXIS(V...)       _IAX_N(TWO_ARGS(V),V)
+
+#define INDEX_OF_AXIS(A,V...)     index_of_axis(A E_OPTARG(V+0))
 
 // Bit mask for a matching enable pin, or 0
 constexpr uint16_t ena_same(const uint8_t a, const uint8_t b) {