output_pin: Improve GCodeRequestQueue timing on duplicate requests

If there is a duplicate request it is not necessary to add a 100ms
delay to the next update.  Rework the callback signaling to better
report these duplicate updates.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 19 insertions, 13 deletions

diff --git a/klippy/extras/output_pin.py b/klippy/extras/output_pin.py
index 3d7a952c..2c5cae9c 100644
--- a/klippy/extras/output_pin.py
+++ b/klippy/extras/output_pin.py
@@ -32,12 +32,18 @@ class GCodeRequestQueue:
                 pos += 1
             req_pt, req_val = rqueue[pos]
             # Invoke callback for the request
-            want_dequeue, min_wait_time = self.callback(next_time, req_val)
-            self.next_min_flush_time = next_time + max(min_wait_time,
-                                                       PIN_MIN_TIME)
-            if want_dequeue:
-                pos += 1
-            del rqueue[:pos]
+            min_wait = 0.
+            ret = self.callback(next_time, req_val)
+            if ret is not None:
+                # Handle special cases
+                action, min_wait = ret
+                if action == "discard":
+                    del rqueue[:pos+1]
+                    continue
+                if action == "delay":
+                    pos -= 1
+            del rqueue[:pos+1]
+            self.next_min_flush_time = next_time + max(min_wait, PIN_MIN_TIME)
             # Ensure following queue items are flushed
             self.toolhead.note_mcu_movequeue_activity(self.next_min_flush_time)
     def queue_request(self, print_time, value):
@@ -82,13 +88,13 @@ class PrinterOutputPin:
     def get_status(self, eventtime):
         return {'value': self.last_value}
     def _set_pin(self, print_time, value):
-        if value != self.last_value:
-            self.last_value = value
-            if self.is_pwm:
-                self.mcu_pin.set_pwm(print_time, value)
-            else:
-                self.mcu_pin.set_digital(print_time, value)
-        return (True, 0.)
+        if value == self.last_value:
+            return "discard", 0.
+        self.last_value = value
+        if self.is_pwm:
+            self.mcu_pin.set_pwm(print_time, value)
+        else:
+            self.mcu_pin.set_digital(print_time, value)
     cmd_SET_PIN_help = "Set the value of an output pin"
     def cmd_SET_PIN(self, gcmd):
         # Read requested value