PR: Enable multiple z_thermal_adjust sections

Multiple `z_thermal_adjust` sections may now be defined in config to compensate for different sources of z thermal expansion that happen at different rates.

Signed-off-by: Gareth Farrington <gareth@waves.ky>

docs/Config_Reference.md

@@ -1240,7 +1240,9 @@ the nature of skew correction these lengths are set via gcode. See
 Temperature-dependant toolhead Z position adjustment. Compensate for vertical
 toolhead movement caused by thermal expansion of the printer's frame in
 real-time using a temperature sensor (typically coupled to a vertical section
-of frame).
+of frame). Multiple sections may be defined as [z_thermal_adjust component] to
+compensate for thermal expansion in different printer components, such as the
+hotend, heatbreak and frame.
 
 See also: [extended g-code commands](G-Codes.md#z_thermal_adjust).
 

docs/G-Codes.md

@@ -1486,15 +1486,19 @@ The following commands are available when the
 is enabled.
 
 #### SET_Z_THERMAL_ADJUST
-`SET_Z_THERMAL_ADJUST [ENABLE=<0:1>] [TEMP_COEFF=<value>] [REF_TEMP=<value>]`:
-Enable or disable the Z thermal adjustment with `ENABLE`. Disabling does not
+`SET_Z_THERMAL_ADJUST [COMPONENT=name] [ENABLE=<0:1>] [TEMP_COEFF=<value>]
+ [REF_TEMP=<value>]`:
+- `COMPONENT`: if multiple thermal adjustments are defined use `COMPONENT` to
+specify which one to adjust.
+- `ENABLE`: Enable or disable the Z thermal adjustment. Disabling does not
 remove any adjustment already applied, but will freeze the current adjustment
 value - this prevents potentially unsafe downward Z movement. Re-enabling can
 potentially cause upward tool movement as the adjustment is updated and applied.
-`TEMP_COEFF` allows run-time tuning of the adjustment temperature coefficient
+- `TEMP_COEFF`: allows run-time tuning of the adjustment temperature coefficient
 (i.e. the `TEMP_COEFF` config parameter). `TEMP_COEFF` values are not saved to
-the config. `REF_TEMP` manually overrides the reference temperature typically
-set during homing (for use in e.g. non-standard homing routines) - will be reset
+the config.
+- `REF_TEMP` manually overrides the reference temperature typically set during
+homing (for use in e.g. non-standard homing routines) - will be reset
 automatically upon homing.
 
 ### [z_tilt]

klippy/extras/z_thermal_adjust.py

@@ -56,8 +56,15 @@ class ZThermalAdjuster:
         self.next_transform = None
 
         # Register gcode commands
-        self.gcode.register_command('SET_Z_THERMAL_ADJUST',
-                                    self.cmd_SET_Z_THERMAL_ADJUST,
+        full_name = config.get_name()
+        self.component = None
+        if not full_name == "z_thermal_adjust":
+            self.component = full_name.split(maxsplit=1)[-1]
+        self.register_commands(self.component)
+
+    def register_commands(self, component):
+        self.gcode.register_mux_command("SET_Z_THERMAL_ADJUST", "COMPONENT",
+                                    component, self.cmd_SET_Z_THERMAL_ADJUST,
                                     desc=self.cmd_SET_Z_THERMAL_ADJUST_help)
 
     def handle_connect(self):
@@ -169,13 +176,18 @@ class ZThermalAdjuster:
 
         state = '1 (enabled)' if self.adjust_enable else '0 (disabled)'
         override = ' (manual)' if self.ref_temp_override else ''
-        msg = ("enable: %s\n"
+        component = ''
+        if not self.component is None:
+            component = "component: %s\n" % (self.component,)
+        msg = ("%s"
+               "enable: %s\n"
                "temp_coeff: %f mm/degC\n"
                "ref_temp: %.2f degC%s\n"
                "-------------------\n"
                "Current Z temp: %.2f degC\n"
                "Applied Z adjustment: %.4f mm"
-               % (state,
+               % (component,
+                  state,
                   self.temp_coeff,
                   self.ref_temperature, override,
                   self.smoothed_temp,
@@ -185,5 +197,8 @@ class ZThermalAdjuster:
 
     cmd_SET_Z_THERMAL_ADJUST_help = 'Set/query Z Thermal Adjust parameters.'
 
+def load_config_prefix(config):
+    return ZThermalAdjuster(config)
+
 def load_config(config):
     return ZThermalAdjuster(config)