mcu: Provide some further help on common MCU shutdown errors

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

klippy/klippy.py

@@ -242,8 +242,7 @@ class Printer:
     def note_shutdown(self, msg):
         if self.state_message == message_ready:
             self.need_dump_debug = True
-        self.state_message = "Firmware shutdown: %s%s" % (
+        self.state_message = "%s%s" % (msg, message_shutdown)
-            msg, message_shutdown)
         self.gcode.set_printer_ready(False)
     def note_mcu_error(self, msg):
         self.state_message = "%s%s" % (msg, message_restart)

klippy/mcu.py

@@ -475,13 +475,16 @@ class MCU:
         if self.is_shutdown:
             return
         self.is_shutdown = True
-        self._shutdown_msg = params['#msg']
+        self._shutdown_msg = msg = params['#msg']
         logging.info("%s: %s" % (params['#name'], self._shutdown_msg))
         pst = self._print_start_time
         logging.info("Clock last synchronized at %.6f (%d)" % (
             pst, int(pst * self._mcu_freq)))
         self.serial.dump_debug()
-        self._printer.note_shutdown(self._shutdown_msg)
+        prefix = "MCU shutdown: "
+        if params['#name'] == 'is_shutdown':
+            prefix = "Previous MCU shutdown: "
+        self._printer.note_shutdown(prefix + msg + error_help(msg))
     # Connection phase
     def _check_restart(self, reason):
         start_reason = self._printer.get_start_args().get("start_reason")
@@ -742,5 +745,28 @@ class MCU:
     def __del__(self):
         self.disconnect()
 
+Common_MCU_errors = {
+    ("Timer too close", "No next step", "Missed scheduling of next "): """
+This is generally indicative of an intermittent
+communication failure.""",
+    ("ADC out of range",): """
+This generally occurs when a heater temperature exceeds
+it's configured min_temp or max_temp.""",
+    ("Rescheduled timer in the past", "Stepper too far in past"): """
+This generally occurs when the micro-controller has been
+requested to step at a rate higher than it is capable of
+obtaining.""",
+    ("Command request",): """
+This generally occurs in response to an M112 G-Code command
+or in response to an internal error in the host software.""",
+}
+
+def error_help(msg):
+    for prefixes, help_msg in Common_MCU_errors.items():
+        for prefix in prefixes:
+            if msg.startswith(prefix):
+                return help_msg
+    return ""
+
 def add_printer_objects(printer, config):
     printer.add_object('mcu', MCU(printer, config.getsection('mcu')))

src/adccmds.c

@@ -43,7 +43,7 @@ analog_in_event(struct timer *timer)
         return SF_RESCHEDULE;
     }
     if (a->value < a->min_value || a->value > a->max_value)
-        shutdown("adc out of range");
+        shutdown("ADC out of range");
     sched_wake_task(&analog_wake);
     a->next_begin_time += a->rest_time;
     a->timer.waketime = a->next_begin_time;

src/basecmd.c

@@ -297,7 +297,7 @@ stats_update(uint32_t start, uint32_t cur)
 void
 command_emergency_stop(uint32_t *args)
 {
-    shutdown("command request");
+    shutdown("Command request");
 }
 DECL_COMMAND_FLAGS(command_emergency_stop, HF_IN_SHUTDOWN, "emergency_stop");
 

src/stepper.c

@@ -79,7 +79,7 @@ stepper_load_next(struct stepper *s, uint32_t min_next_time)
         if (unlikely(timer_is_before(s->next_step_time, min_next_time))) {
             if ((int32_t)(s->next_step_time - min_next_time)
                 < (int32_t)(-timer_from_us(1000)))
-                shutdown("stepper too far in past");
+                shutdown("Stepper too far in past");
             s->time.waketime = min_next_time;
         } else {
             s->time.waketime = s->next_step_time;