chipmisc: Add support for output pins set at runtime

Add the ability to define output pins that may be set at runtime with
a new SET_PIN extended g-code command.

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

2 files changed, 115 insertions, 34 deletions

diff --git a/config/example-extras.cfg b/config/example-extras.cfg
index 67b725b4..19405262 100644
--- a/config/example-extras.cfg
+++ b/config/example-extras.cfg
@@ -95,28 +95,49 @@
 #   seconds.
 
 
+# Run-time configurable digital output pins (one may define any number
+# of sections with a "digital_output" prefix). Pins configured here
+# will be setup as digital outputs and one may modify them at run-time
+# using the "SET_PIN PIN=my_pin VALUE=0" extended g-code command.
+#[digital_output my_pin]
+#pin:
+#   The pin to configure as a digital output. This parameter must be
+#   provided.
+#value:
+#   The value to initially set the pin to during MCU configuration
+#   (either 0 or 1). The default is 0 (for low voltage).
+#shutdown_value:
+#   The value to set the pin to on an MCU shutdown event. The default
+#   is 0 (for low voltage).
+
 # Statically configured digital output pins (one may define any number
 # of sections with a "static_digital_output" prefix). Pins configured
-# here will be setup as a GPIO output during MCU configuration.
+# here will be setup as a GPIO output during MCU configuration. They
+# can not be changed at run-time.
 #[static_digital_output my_output_pins]
 #pins:
 #   A comma separated list of pins to be set as GPIO output pins. The
 #   pin will be set to a high level unless the pin name is prefaced
 #   with "!". This parameter must be provided.
 
-
-# Statically configured PWM output pins (one may define any number of
-# sections with a "static_pwm_output" prefix). Pins configured here
-# will be setup as PWM outputs during MCU configuration.
-#[static_pwm_output my_output_pwm]
+# Run-time configurable PWM (pulse width modulator) output pins (one
+# may define any number of sections with a "pwm_output" prefix). Pins
+# configured here will be setup as PWM outputs and one may modify them
+# at run-time using the "SET_PIN PIN=my_pin VALUE=.1" extended g-code
+# command.
+#[pwm_output my_pin]
 #pin:
-#   The pin to configure as PWM output. This parameter must be
+#   The pin to configure as a PWM output. This parameter must be
 #   provided.
 #value:
-#   The value to statically set the PWM output to. This is typically
-#   set to a number between 0.0 and 1.0 with 1.0 being full on and 0.0
-#   being full off. However, the range may be changed with the 'scale'
-#   parameter (see below). This parameter must be provided.
+#   The value to initially set the PWM output to during MCU
+#   configuration. This is typically set to a number between 0.0 and
+#   1.0 with 1.0 being full on and 0.0 being full off. However, the
+#   range may be changed with the 'scale' parameter (see below). The
+#   default is 0.
+#shutdown_value:
+#   The value to set the pin to on an MCU shutdown event. The default
+#   is 0.
 #hard_pwm:
 #   Set this value to force hardware PWM instead of software PWM. Set
 #   to 1 to force a hardware PWM at the fastest rate; set to a higher
@@ -126,14 +147,26 @@
 #   The amount of time (in seconds) per PWM cycle when using software
 #   based PWM. The default is 0.100 seconds.
 #scale:
-#   This parameter can be used to alter how the 'value' parameter is
-#   interpreted. If provided, then the 'value' parameter should be
-#   between 0.0 and 'scale'. This may be useful when configuring a PWM
-#   pin that controls a stepper voltage reference. The 'scale' can be
-#   set to the equivalent stepper amperage if the PWM were fully
-#   enabled, and then the 'value' parameter can be specified using the
-#   desired amperage for the stepper. The default is to not scale the
-#   'value' parameter.
+#   This parameter can be used to alter how the 'value' and
+#   'shutdown_value' parameters are interpreted. If provided, then the
+#   'value' parameter should be between 0.0 and 'scale'. This may be
+#   useful when configuring a PWM pin that controls a stepper voltage
+#   reference. The 'scale' can be set to the equivalent stepper
+#   amperage if the PWM were fully enabled, and then the 'value'
+#   parameter can be specified using the desired amperage for the
+#   stepper. The default is to not scale the 'value' parameter.
+
+# Statically configured PWM output pins (one may define any number of
+# sections with a "static_pwm_output" prefix). Pins configured here
+# will be setup as PWM outputs during MCU configuration. They can not
+# be changed at run-time.
+#[static_pwm_output my_output_pwm]
+#pin:
+#value:
+#hard_pwm:
+#cycle_time:
+#scale:
+#    See the 'pwm_output' section for details on these parameters.
 
 
 # Statically configured AD5206 digipots connected via SPI bus (one may
diff --git a/klippy/chipmisc.py b/klippy/chipmisc.py
index 0c41f9d4..6fae2868 100644
--- a/klippy/chipmisc.py
+++ b/klippy/chipmisc.py
@@ -7,7 +7,7 @@ import pins, mcu
 
 
 ######################################################################
-# Statically configured output pins
+# Output pins
 ######################################################################
 
 class PrinterStaticDigitalOut:
@@ -17,26 +17,70 @@ class PrinterStaticDigitalOut:
             mcu_pin = pins.setup_pin(printer, 'digital_out', pin_desc)
             mcu_pin.setup_static()
 
-class PrinterStaticPWM:
+PIN_MIN_TIME = 0.100
+
+class PrinterPin:
     def __init__(self, printer, config):
-        mcu_pwm = pins.setup_pin(printer, 'pwm', config.get('pin'))
-        mcu_pwm.setup_max_duration(0.)
-        hard_pwm = config.getint('hard_pwm', None, minval=1)
-        if hard_pwm is None:
-            mcu_pwm.setup_cycle_time(config.getfloat(
-                'cycle_time', 0.100, above=0.))
+        self.printer = printer
+        self.is_pwm = 'pwm' in config.section.split()[0]
+        if self.is_pwm:
+            self.mcu_pin = pins.setup_pin(printer, 'pwm', config.get('pin'))
+            hard_pwm = config.getint('hard_pwm', None, minval=1)
+            if hard_pwm is None:
+                self.mcu_pin.setup_cycle_time(config.getfloat(
+                    'cycle_time', 0.100, above=0.))
+            else:
+                self.mcu_pin.setup_hard_pwm(hard_pwm)
+            self.scale = config.getfloat('scale', 1., above=0.)
         else:
-            mcu_pwm.setup_hard_pwm(hard_pwm)
-        scale = config.getfloat('scale', 1., above=0.)
-        value = config.getfloat('value', minval=0., maxval=scale)
-        mcu_pwm.setup_static_pwm(value / scale)
+            self.mcu_pin = pins.setup_pin(
+                printer, 'digital_out', config.get('pin'))
+            self.scale = 1.
+        self.mcu_pin.setup_max_duration(0.)
+        self.last_value_time = 0.
+        self.last_value = config.getfloat(
+            'value', 0., minval=0., maxval=self.scale)
+        self.is_static = config.section.startswith('static_')
+        if self.is_static:
+            self.mcu_pin.setup_static_pwm(self.last_value / self.scale)
+        else:
+            self.mcu_pin.setup_start_value(
+                self.last_value, config.getfloat('shutdown_value', 0.,
+                                                 minval=0., maxval=self.scale))
+        self.gcode = printer.objects['gcode']
+        self.gcode.register_command("SET_PIN", self.cmd_SET_PIN,
+                                    desc=self.cmd_SET_PIN_help)
+    cmd_SET_PIN_help = "Set the value of an output pin"
+    def cmd_SET_PIN(self, params):
+        pin_name = self.gcode.get_str('PIN', params)
+        pin = self.printer.objects.get('pin ' + pin_name)
+        if pin is not self:
+            if pin is None:
+                raise self.gcode.error("Pin not configured")
+            return pin.cmd_SET_PIN(params)
+        if self.is_static:
+            raise self.gcode.error("Static pin can not be changed at run-time")
+        value = self.gcode.get_float('VALUE', params)
+        if value == self.last_value:
+            return
+        print_time = self.printer.objects['toolhead'].get_last_move_time()
+        print_time = max(print_time, self.last_value_time + PIN_MIN_TIME)
+        if self.is_pwm:
+            if value < 0. or value > self.scale:
+                raise self.gcode.error("Invalid pin value")
+            self.mcu_pin.set_pwm(print_time, value)
+        else:
+            if value not in [0., 1.]:
+                raise self.gcode.error("Invalid pin value")
+            self.mcu_pin.set_digital(print_time, value)
+        self.last_value = value
+        self.last_value_time = print_time
 
 
 ######################################################################
 # Servos
 ######################################################################
 
-SERVO_MIN_TIME = 0.100
 SERVO_SIGNAL_PERIOD = 0.020
 
 class PrinterServo:
@@ -60,7 +104,7 @@ class PrinterServo:
     def set_pwm(self, print_time, value):
         if value == self.last_value:
             return
-        print_time = max(self.last_value_time + SERVO_MIN_TIME, print_time)
+        print_time = max(print_time, self.last_value_time + PIN_MIN_TIME)
         self.mcu_servo.set_pwm(print_time, value)
         self.last_value = value
         self.last_value_time = print_time
@@ -300,8 +344,12 @@ def add_printer_objects(printer, config):
             printer, config.getsection('replicape')))
     for s in config.get_prefix_sections('static_digital_output '):
         printer.add_object(s.section, PrinterStaticDigitalOut(printer, s))
+    for s in config.get_prefix_sections('digital_output '):
+        printer.add_object('pin' + s.section[14:], PrinterPin(printer, s))
     for s in config.get_prefix_sections('static_pwm_output '):
-        printer.add_object(s.section, PrinterStaticPWM(printer, s))
+        printer.add_object('pin' + s.section[17:], PrinterPin(printer, s))
+    for s in config.get_prefix_sections('pwm_output '):
+        printer.add_object('pin' + s.section[10:], PrinterPin(printer, s))
     for s in config.get_prefix_sections('servo '):
         printer.add_object(s.section, PrinterServo(printer, s))
     for s in config.get_prefix_sections('ad5206 '):