Merge pull request #382 from bdring/Devt

Devt

Grbl_Esp32/grbl.h

@@ -20,7 +20,7 @@
 
 // Grbl versioning system
 #define GRBL_VERSION "1.1f"
-#define GRBL_VERSION_BUILD "20200417"
+#define GRBL_VERSION_BUILD "20200419"
 
 //#include <sdkconfig.h>
 #include <Arduino.h>

Grbl_Esp32/spindle_control.cpp

@@ -56,7 +56,7 @@ void spindle_init() {
     pinMode(SPINDLE_DIR_PIN, OUTPUT);
 #endif
     // use the LED control feature to setup PWM   https://docs.espressif.com/projects/esp-idf/en/latest/api-reference/peripherals/ledc.html
-    spindle_pwm_chan_num = sys_get_next_PWM_chan_num();
+    spindle_pwm_chan_num = 0; // spindle always uses channel 0
     ledcSetup(spindle_pwm_chan_num, (double)settings.spindle_pwm_freq, SPINDLE_PWM_BIT_PRECISION); // setup the channel
     ledcAttachPin(SPINDLE_PWM_PIN, spindle_pwm_chan_num); // attach the PWM to the pin
     // Start with spindle off off

Grbl_Esp32/system.cpp

@@ -589,12 +589,20 @@ int8_t sys_get_next_RMT_chan_num() {
     }
 }
 
+/*
+    This returns an unused pwm channel.
+    The 8 channels share 4 timers, so pairs 0,1 & 2,3 , etc
+    have to be the same frequency. The spindle always uses channel 0
+    so we start counting from 2.
+    There are still possible issues if requested channels use different frequencies
+    TODO: Make this more robust.
+*/
 int8_t sys_get_next_PWM_chan_num() {
-    static uint8_t next_PWM_chan_num = 0; // channels 0-7 are valid
+    static uint8_t next_PWM_chan_num = 2; // start at 2 to avoid spindle
     if (next_PWM_chan_num < 8)  // 7 is the max PWM channel number
         return next_PWM_chan_num++;
     else {
         grbl_msg_sendf(CLIENT_SERIAL, MSG_LEVEL_ERROR, "Error: out of PWM channels");
         return -1;
     }
-}
+}