menu: initial support for analog buttons (#977)

Signed-off-by: Janar Sööt <janar.soot@gmail.com>

3 files changed, 204 insertions, 16 deletions

diff --git a/config/example-extras.cfg b/config/example-extras.cfg
index a75f8b10..6adf0592 100644
--- a/config/example-extras.cfg
+++ b/config/example-extras.cfg
@@ -1249,19 +1249,46 @@
 #   using encoder. This parameter must be provided when using menu.
 #click_pin:
 #   The pin connected to 'enter' button or encoder 'click'. This parameter
-#   must be provided when using menu.
+#   must be provided when using menu. The presence of an 'analog_range_click_pin'
+#   config parameter turns this parameter from digital to analog.
 #back_pin:
 #   The pin connected to 'back' button. This parameter is optional, menu
-#   can be used without it.
+#   can be used without it. The presence of an 'analog_range_back_pin'
+#   config parameter turns this parameter from digital to analog.
 #up_pin:
 #   The pin connected to 'up' button. This parameter must be provided
-#   when using menu without encoder.
+#   when using menu without encoder. The presence of an 'analog_range_up_pin'
+#   config parameter turns this parameter from digital to analog.
 #down_pin:
 #   The pin connected to 'down' button. This parameter must be provided
-#   when using menu without encoder.
+#   when using menu without encoder. The presence of an 'analog_range_down_pin'
+#   config parameter turns this parameter from digital to analog.
 #kill_pin:
-#   The pin connected to 'kill' button. This button will call
-#   emergency stop.
+#   The pin connected to 'kill' button. This button will call emergency stop.
+#   The presence of an 'analog_range_kill_pin' config parameter turns this
+#   parameter from digital to analog.
+#analog_pullup_resistor: 4700
+#   The resistance (in ohms) of the pullup attached to the analog button.
+#   The default is 4700 ohms.
+#analog_pin_debug:
+#   When enabled it will output analog (ADC) button readings to the log.
+#   It's useful for finding analog button resistance range values.
+#   The default is False (disabled)
+#analog_range_click_pin:
+#   The resistance range for a 'enter' button. Range minimum and maximum
+#   comma-separated values must be provided when using analog button.
+#analog_range_back_pin:
+#   The resistance range for a 'back' button. Range minimum and maximum
+#   comma-separated values must be provided when using analog button.
+#analog_range_up_pin:
+#   The resistance range for a 'up' button. Range minimum and maximum
+#   comma-separated values must be provided when using analog button.
+#analog_range_down_pin:
+#   The resistance range for a 'down' button. Range minimum and maximum
+#   comma-separated values must be provided when using analog button.
+#analog_range_kill_pin:
+#   The resistance range for a 'kill' button. Range minimum and maximum
+#   comma-separated values must be provided when using analog button.
 
 
 # Custom thermistors (one may define any number of sections with a
diff --git a/klippy/extras/buttons.py b/klippy/extras/buttons.py
index 9ebd3adc..b06f1f83 100644
--- a/klippy/extras/buttons.py
+++ b/klippy/extras/buttons.py
@@ -7,6 +7,10 @@ import logging
 
 QUERY_TIME = .002
 RETRANSMIT_COUNT = 50
+ADC_REPORT_TIME = 0.015
+ADC_DEBOUNCE_TIME = 0.025
+ADC_SAMPLE_TIME = 0.001
+ADC_SAMPLE_COUNT = 6
 
 # Rotary encoder handler https://github.com/brianlow/Rotary
 # Copyright 2011 Ben Buxton (bb@cactii.net).
@@ -112,6 +116,79 @@ class MCU_buttons:
         self.last_button = button
 
 
+class MCU_ADC_buttons:
+    def __init__(self, printer, pin, pullup, debug=False):
+        self.reactor = printer.get_reactor()
+        self.buttons = []
+        self.last_button = None
+        self.last_pressed = None
+        self.last_debouncetime = 0
+        self.pullup = pullup
+        self.debug = debug
+        self.pin = pin
+        self.min_value = self.max_value = None
+        ppins = printer.lookup_object('pins')
+        self.mcu_adc = ppins.setup_pin('adc', self.pin)
+        self.mcu_adc.setup_minmax(ADC_SAMPLE_TIME, ADC_SAMPLE_COUNT)
+        self.mcu_adc.setup_adc_callback(ADC_REPORT_TIME, self.adc_callback)
+
+    def setup_button(self, min_value, max_value, callback):
+        if self.min_value is None:
+            self.min_value = min_value
+        else:
+            self.min_value = min(self.min_value, min_value)
+
+        if self.max_value is None:
+            self.max_value = max_value
+        else:
+            self.max_value = max(self.max_value, max_value)
+
+        self.buttons.append((min_value, max_value, callback))
+
+    def adc_callback(self, read_time, read_value):
+        adc = max(.00001, min(.99999, read_value))
+        r = self.pullup * adc / (1.0 - adc)
+        self.reactor.register_async_callback(
+            (lambda e, s=self, v=r: s.handle_button(e, v)))
+
+    def get_button(self, value):
+        if (self.min_value is not None and self.max_value is not None
+                and self.min_value <= value <= self.max_value):
+            for i, (min_value, max_value, cb) in enumerate(self.buttons):
+                if min_value < value < max_value:
+                    return i
+        return None
+
+    def handle_button(self, eventtime, value):
+        btn = self.get_button(int(value))
+
+        # If the button changed, due to noise or pressing:
+        if btn != self.last_button:
+            # reset the debouncing timer
+            self.last_debouncetime = eventtime
+
+        # button debounce check & new button pressed
+        if ((eventtime - self.last_debouncetime) >= ADC_DEBOUNCE_TIME
+                and self.last_button == btn and self.last_pressed != btn):
+                # release last_pressed
+                if self.last_pressed is not None:
+                    self.call_button(eventtime, self.last_pressed, False)
+                    self.last_pressed = None
+                if btn is not None:
+                    self.call_button(eventtime, btn, True)
+                    self.last_pressed = btn
+
+        self.last_button = btn
+        if self.debug is True:
+            logging.info(
+                "analog pin: %s value: %d" % (self.pin, int(value)))
+
+    def call_button(self, eventtime, button, state):
+        if button < len(self.buttons):
+            minval, maxval, callback = self.buttons[button]
+            callback(eventtime, state)
+
+
 ######################################################################
 # Rotary Encoders
 ######################################################################
@@ -138,6 +215,20 @@ class PrinterButtons:
     def __init__(self, config):
         self.printer = config.get_printer()
         self.mcu_buttons = {}
+        self.adc_buttons = {}
+    def register_adc_button(
+            self, pin, min_val, max_val, pullup, callback, debug=False):
+        adc_buttons = self.adc_buttons.get(pin)
+        if adc_buttons is None:
+            self.adc_buttons[pin] = adc_buttons = MCU_ADC_buttons(
+                self.printer, pin, pullup, debug)
+        adc_buttons.setup_button(min_val, max_val, callback)
+    def register_adc_button_push(
+            self, pin, min_val, max_val, pullup, callback, debug=False):
+        def helper(eventtime, state, callback=callback):
+            if state:
+                callback(eventtime)
+        self.register_adc_button(pin, min_val, max_val, pullup, helper, debug)
     def register_buttons(self, pins, callback):
         # Parse pins
         ppins = self.printer.lookup_object('pins')
diff --git a/klippy/extras/display/menu.py b/klippy/extras/display/menu.py
index b3c0ea16..b3a24154 100644
--- a/klippy/extras/display/menu.py
+++ b/klippy/extras/display/menu.py
@@ -1000,7 +1000,21 @@ class MenuManager:
         self.up_pin = config.get('up_pin', None)
         self.down_pin = config.get('down_pin', None)
         self.kill_pin = config.get('kill_pin', None)
+        # analog button ranges
+        self.analog_range_click_pin = config.get(
+            'analog_range_click_pin', None)
+        self.analog_range_back_pin = config.get(
+            'analog_range_back_pin', None)
+        self.analog_range_up_pin = config.get(
+            'analog_range_up_pin', None)
+        self.analog_range_down_pin = config.get(
+            'analog_range_down_pin', None)
+        self.analog_range_kill_pin = config.get(
+            'analog_range_kill_pin', None)
         self._last_click_press = 0
+        self.analog_pullup = config.getfloat(
+            'analog_pullup_resistor', 4700., above=0.)
+        self.analog_pin_debug = config.getboolean('analog_pin_debug', False)
         self._encoder_fast_rate = config.getfloat(
             'encoder_fast_rate', .03, above=0.)
         self._last_encoder_cw_eventtime = 0
@@ -1012,6 +1026,7 @@ class MenuManager:
         self.printer.register_event_handler("klippy:ready", self.handle_ready)
         # register buttons & encoder
         if self.buttons:
+            # digital buttons
             if self.encoder_pins:
                 try:
                     pin1, pin2 = self.encoder_pins.split(',')
@@ -1021,20 +1036,75 @@ class MenuManager:
                     pin1.strip(), pin2.strip(),
                     self.encoder_cw_callback, self.encoder_ccw_callback)
             if self.click_pin:
-                self.buttons.register_buttons(
-                    [self.click_pin], self.click_callback)
+                if self.analog_range_click_pin is not None:
+                    try:
+                        p_min, p_max = map(
+                            float, self.analog_range_click_pin.split(','))
+                    except Exception:
+                        raise config.error(
+                            "Unable to parse analog_range_click_pin")
+                    self.buttons.register_adc_button(
+                        self.click_pin, p_min, p_max, self.analog_pullup,
+                        self.click_callback, self.analog_pin_debug)
+                else:
+                    self.buttons.register_buttons(
+                        [self.click_pin], self.click_callback)
             if self.back_pin:
-                self.buttons.register_button_push(
-                    self.back_pin, self.back_callback)
+                if self.analog_range_back_pin is not None:
+                    try:
+                        p_min, p_max = map(
+                            float, self.analog_range_back_pin.split(','))
+                    except Exception:
+                        raise config.error(
+                            "Unable to parse analog_range_back_pin")
+                    self.buttons.register_adc_button_push(
+                        self.back_pin, p_min, p_max, self.analog_pullup,
+                        self.back_callback, self.analog_pin_debug)
+                else:
+                    self.buttons.register_button_push(
+                        self.back_pin, self.back_callback)
             if self.up_pin:
-                self.buttons.register_button_push(
-                    self.up_pin, self.up_callback)
+                if self.analog_range_up_pin is not None:
+                    try:
+                        p_min, p_max = map(
+                            float, self.analog_range_up_pin.split(','))
+                    except Exception:
+                        raise config.error(
+                            "Unable to parse analog_range_up_pin")
+                    self.buttons.register_adc_button_push(
+                        self.up_pin, p_min, p_max, self.analog_pullup,
+                        self.up_callback, self.analog_pin_debug)
+                else:
+                    self.buttons.register_button_push(
+                        self.up_pin, self.up_callback)
             if self.down_pin:
-                self.buttons.register_button_push(
-                    self.down_pin, self.down_callback)
+                if self.analog_range_down_pin is not None:
+                    try:
+                        p_min, p_max = map(
+                            float, self.analog_range_down_pin.split(','))
+                    except Exception:
+                        raise config.error(
+                            "Unable to parse analog_range_down_pin")
+                    self.buttons.register_adc_button_push(
+                        self.down_pin, p_min, p_max, self.analog_pullup,
+                        self.down_callback, self.analog_pin_debug)
+                else:
+                    self.buttons.register_button_push(
+                        self.down_pin, self.down_callback)
             if self.kill_pin:
-                self.buttons.register_button_push(
-                    self.kill_pin, self.kill_callback)
+                if self.analog_range_kill_pin is not None:
+                    try:
+                        p_min, p_max = map(
+                            float, self.analog_range_kill_pin.split(','))
+                    except Exception:
+                        raise config.error(
+                            "Unable to parse analog_range_kill_pin")
+                    self.buttons.register_adc_button_push(
+                        self.kill_pin, p_min, p_max, self.analog_pullup,
+                        self.kill_callback, self.analog_pin_debug)
+                else:
+                    self.buttons.register_button_push(
+                        self.kill_pin, self.kill_callback)
 
         # Add MENU commands
         self.gcode.register_mux_command("MENU", "DO", 'dump', self.cmd_DO_DUMP,