heaters: make PWM instantaneous

Heaters control is reactive,
the faster we apply new PWM - the better.
Add command to directly apply PWM as fast as it arrives.

Signed-off-by: Timofey Titovets <[email protected]>

klippy/extras/heaters.py

@@ -26,7 +26,6 @@ def __init__(self, config, sensor):
         self.max_temp = config.getfloat('max_temp', above=self.min_temp)
         self.sensor.setup_minmax(self.min_temp, self.max_temp)
         self.sensor.setup_callback(self.temperature_callback)
-        self.pwm_delay = self.sensor.get_report_time_delta()
         # Setup temperature checks
         self.min_extrude_temp = config.getfloat(
             'min_extrude_temp', 170.,
@@ -52,8 +51,9 @@ def __init__(self, config, sensor):
         heater_pin = config.get('heater_pin')
         ppins = self.printer.lookup_object('pins')
         self.mcu_pwm = ppins.setup_pin('pwm', heater_pin)
+        self.pwm_pending_delay = 0.3
         pwm_cycle_time = config.getfloat('pwm_cycle_time', 0.100, above=0.,
-                                         maxval=self.pwm_delay)
+                                         maxval=self.pwm_pending_delay)
         self.mcu_pwm.setup_cycle_time(pwm_cycle_time)
         self.mcu_pwm.setup_max_duration(MAX_HEAT_TIME)
         # Load additional modules
@@ -72,10 +72,11 @@ def set_pwm(self, read_time, value):
             and abs(value - self.last_pwm_value) < 0.05):
             # No significant change in value - can suppress update
             return
-        pwm_time = read_time + self.pwm_delay
-        self.next_pwm_time = pwm_time + 0.75 * MAX_HEAT_TIME
+        # PWM will apply on arrival, expect less then pending delay
+        pwm_time = read_time + self.pwm_pending_delay
+        self.next_pwm_time = pwm_time + 0.7 * MAX_HEAT_TIME
         self.last_pwm_value = value
-        self.mcu_pwm.set_pwm(pwm_time, value)
+        self.mcu_pwm.set_pwm_now(pwm_time, value)
         #logging.debug("%s: pwm=%.3f@%.3f (from %.3f@%.3f [%.3f])",
         #              self.name, value, pwm_time,
         #              self.last_temp, self.last_temp_time, self.target_temp)
@@ -95,8 +96,6 @@ def _handle_shutdown(self):
     # External commands
     def get_name(self):
         return self.name
-    def get_pwm_delay(self):
-        return self.pwm_delay
     def get_max_power(self):
         return self.max_power
     def get_smooth_time(self):

klippy/extras/pid_calibrate.py

@@ -71,7 +71,7 @@ def __init__(self, heater, target):
     def set_pwm(self, read_time, value):
         if value != self.last_pwm:
             self.pwm_samples.append(
-                (read_time + self.heater.get_pwm_delay(), value))
+                (read_time, value))
             self.last_pwm = value
         self.heater.set_pwm(read_time, value)
     def temperature_update(self, read_time, temp, target_temp):

klippy/mcu.py

@@ -473,6 +473,8 @@ def _build_config(self):
             % (self._oid, self._last_clock, svalue), is_init=True)
         self._set_cmd = self._mcu.lookup_command(
             "queue_digital_out oid=%c clock=%u on_ticks=%u", cq=cmd_queue)
+        self._set_now_cmd = self._mcu.lookup_command(
+            "queue_digital_out_now oid=%c clock=%u on_ticks=%u", cq=cmd_queue)
     def set_pwm(self, print_time, value):
         if self._invert:
             value = 1. - value
@@ -481,6 +483,14 @@ def set_pwm(self, print_time, value):
         self._set_cmd.send([self._oid, clock, v],
                            minclock=self._last_clock, reqclock=clock)
         self._last_clock = clock
+    def set_pwm_now(self, print_time, value):
+        if self._invert:
+            value = 1. - value
+        v = int(max(0., min(1., value)) * self._pwm_max + 0.5)
+        clock = self._mcu.print_time_to_clock(print_time)
+        self._set_now_cmd.send([self._oid, clock, v],
+                               minclock=self._last_clock, reqclock=clock)
+        self._last_clock = clock
 
 class MCU_adc:
     def __init__(self, mcu, pin_params):

src/gpiocmds.c

@@ -174,6 +174,20 @@ command_queue_digital_out(uint32_t *args)
 DECL_COMMAND(command_queue_digital_out,
              "queue_digital_out oid=%c clock=%u on_ticks=%u");
 
+void command_queue_digital_out_now(uint32_t *args)
+{
+    uint32_t oid = args[0];
+    uint32_t time = args[1];
+    uint32_t on_duration = args[2];
+    uint32_t time_now = timer_read_time() + timer_from_us(1000);
+    if (timer_is_before(time_now, time))
+        time = time_now;
+    uint32_t new_args[] = {oid, time, on_duration};
+    command_queue_digital_out(new_args);
+}
+DECL_COMMAND(command_queue_digital_out_now,
+             "queue_digital_out_now oid=%c clock=%u on_ticks=%u");
+
 void
 command_update_digital_out(uint32_t *args)
 {