extruder_stepper: Initial support for synchronized extruder steppers

Signed-off-by: Simo Apell <simo.apell@live.fi>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

test/klippy/extruders.cfg

@@ -0,0 +1,63 @@
+# Config for extruder testing
+[stepper_x]
+step_pin: ar54
+dir_pin: ar55
+enable_pin: !ar38
+step_distance: .0125
+endstop_pin: ^ar3
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_y]
+step_pin: ar60
+dir_pin: !ar61
+enable_pin: !ar56
+step_distance: .0125
+endstop_pin: ^ar14
+position_endstop: 0
+position_max: 200
+homing_speed: 50
+
+[stepper_z]
+step_pin: ar46
+dir_pin: ar48
+enable_pin: !ar62
+step_distance: .0025
+endstop_pin: ^ar18
+position_endstop: 0.5
+position_max: 200
+
+[extruder]
+step_pin: ar26
+dir_pin: ar28
+enable_pin: !ar24
+step_distance: .004242
+nozzle_diameter: 0.500
+filament_diameter: 3.500
+heater_pin: ar10
+sensor_type: EPCOS 100K B57560G104F
+sensor_pin: analog13
+control: pid
+pid_Kp: 22.2
+pid_Ki: 1.08
+pid_Kd: 114
+min_temp: 0
+max_temp: 210
+
+[extruder_stepper my_extra_stepper]
+step_pin: ar8
+dir_pin: ar9
+enable_pin: !ar11
+step_distance: .002
+
+[mcu]
+serial: /dev/ttyACM0
+pin_map: arduino
+
+[printer]
+kinematics: cartesian
+max_velocity: 300
+max_accel: 3000
+max_z_velocity: 5
+max_z_accel: 100

test/klippy/extruders.test

@@ -0,0 +1,13 @@
+# Extruder tests
+DICTIONARY atmega2560.dict
+CONFIG extruders.cfg
+
+# Extrude only
+G1 E5
+G1 E-2
+G1 E7
+
+# Home and extrusion moves
+G28
+G1 X20 Y20 Z1
+G1 X25 Y25 E7.5