query_adc: Add a new module to help query and debug analog pins

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

5 files changed, 50 insertions, 0 deletions

diff --git a/docs/G-Codes.md b/docs/G-Codes.md
index b01d6487..7cd4b02b 100644
--- a/docs/G-Codes.md
+++ b/docs/G-Codes.md
@@ -101,6 +101,11 @@ The following standard commands are supported:
 - `QUERY_ENDSTOPS`: Probe the axis endstops and report if they are
   "triggered" or in an "open" state. This command is typically used to
   verify that an endstop is working correctly.
+- `QUERY_ADC [NAME=<config_name>] [PULLUP=<value>]`: Report the last
+  analog value received for a configured analog pin. If NAME is not
+  provided, the list of available adc names are reported. If PULLUP is
+  provided (as a value in Ohms), the raw analog value along with the
+  equivalent resistance given that pullup is reported.
 - `GET_POSITION`: Return information on the current location of the
   toolhead.
 - `SET_GCODE_OFFSET [X=<pos>|X_ADJUST=<adjust>]
diff --git a/klippy/extras/adc_temperature.py b/klippy/extras/adc_temperature.py
index 2e333792..7a4cc8d2 100644
--- a/klippy/extras/adc_temperature.py
+++ b/klippy/extras/adc_temperature.py
@@ -22,6 +22,8 @@ class PrinterADCtoTemperature:
         ppins = config.get_printer().lookup_object('pins')
         self.mcu_adc = ppins.setup_pin('adc', config.get('sensor_pin'))
         self.mcu_adc.setup_adc_callback(REPORT_TIME, self.adc_callback)
+        query_adc = config.get_printer().try_load_module(config, 'query_adc')
+        query_adc.register_adc(config.get_name(), self.mcu_adc)
     def setup_callback(self, temperature_callback):
         self.temperature_callback = temperature_callback
     def get_report_time_delta(self):
diff --git a/klippy/extras/buttons.py b/klippy/extras/buttons.py
index 5d5aac46..9eeee78e 100644
--- a/klippy/extras/buttons.py
+++ b/klippy/extras/buttons.py
@@ -107,6 +107,8 @@ class MCU_ADC_buttons:
         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)
+        query_adc = printer.lookup_object('query_adc')
+        query_adc.register_adc('adc_button:' + pin.strip(), self.mcu_adc)
 
     def setup_button(self, min_value, max_value, callback):
         self.min_value = min(self.min_value, min_value)
@@ -205,6 +207,7 @@ class RotaryEncoder:
 class PrinterButtons:
     def __init__(self, config):
         self.printer = config.get_printer()
+        self.printer.try_load_module(config, 'query_adc')
         self.mcu_buttons = {}
         self.adc_buttons = {}
     def register_adc_button(self, pin, min_val, max_val, pullup, callback):
diff --git a/klippy/extras/query_adc.py b/klippy/extras/query_adc.py
new file mode 100644
index 00000000..eb065396
--- /dev/null
+++ b/klippy/extras/query_adc.py
@@ -0,0 +1,36 @@
+# Utility for querying the current state of adc pins
+#
+# Copyright (C) 2019  Kevin O'Connor <kevin@koconnor.net>
+#
+# This file may be distributed under the terms of the GNU GPLv3 license.
+
+class QueryADC:
+    def __init__(self, config):
+        self.printer = config.get_printer()
+        self.adc = {}
+        gcode = self.printer.lookup_object('gcode')
+        gcode.register_command("QUERY_ADC", self.cmd_QUERY_ADC,
+                               desc=self.cmd_QUERY_ADC_help)
+    def register_adc(self, name, mcu_adc):
+        self.adc[name] = mcu_adc
+    cmd_QUERY_ADC_help = "Report the last value of an analog pin"
+    def cmd_QUERY_ADC(self, params):
+        gcode = self.printer.lookup_object('gcode')
+        name = gcode.get_str('NAME', params, None)
+        if name not in self.adc:
+            objs = ['"%s"' % (n,) for n in sorted(self.adc.keys())]
+            msg = "Available ADC objects: %s" % (', '.join(objs),)
+            gcode.respond_info(msg)
+            return
+        value, timestamp = self.adc[name].get_last_value()
+        msg = 'ADC object "%s" has value %.6f (timestamp %.3f)' % (
+            name, value, timestamp)
+        pullup = gcode.get_float('PULLUP', params, None, above=0.)
+        if pullup is not None:
+            v = max(.00001, min(.99999, value))
+            r = pullup * v / (1.0 - v)
+            msg += "\n resistance %.3f (with %.0f pullup)" % (r, pullup)
+        gcode.respond_info(msg)
+
+def load_config(config):
+    return QueryADC(config)
diff --git a/klippy/mcu.py b/klippy/mcu.py
index dda02598..0a283452 100644
--- a/klippy/mcu.py
+++ b/klippy/mcu.py
@@ -392,6 +392,7 @@ class MCU_adc:
         self._sample_time = self._report_time = 0.
         self._sample_count = self._range_check_count = 0
         self._report_clock = 0
+        self._last_state = (0., 0.)
         self._oid = self._callback = None
         self._mcu.register_config_callback(self._build_config)
         self._inv_max_adc = 0.
@@ -407,6 +408,8 @@ class MCU_adc:
     def setup_adc_callback(self, report_time, callback):
         self._report_time = report_time
         self._callback = callback
+    def get_last_value(self):
+        return self._last_state
     def _build_config(self):
         if not self._sample_count:
             return
@@ -435,6 +438,7 @@ class MCU_adc:
         next_clock = self._mcu.clock32_to_clock64(params['next_clock'])
         last_read_clock = next_clock - self._report_clock
         last_read_time = self._mcu.clock_to_print_time(last_read_clock)
+        self._last_state = (last_value, last_read_time)
         if self._callback is not None:
             self._callback(last_read_time, last_value)