This feature allows the printer to read the filament diameter
automatically and adjust the printer in real time. Added code to read
an analog voltage that represents a filament diameter measurement. This
measurement is delayed in a ring buffer to compensate for sensors that
are a distance away from the extruder. The measurement is used to
adjust the volumetric_multiplier for the extruder. Some additional g
codes (M404, M405, M406, M407) are used to set parameters and turn
on/off the control. g code M221 is updated. Pins for RAMPS1.4, RAMBO,
and Printrboard are identified for analog input. The configuration file
is updated with relevant user parameters.
#define FILAMENT_SENSOR_EXTRUDER_NUM 0 //The number of the extruder that has the filament sensor (0,1,2)
#define MEASUREMENT_DELAY_CM 14 //measurement delay in cm. This is the distance from filament sensor to middle of barrel
#define DEFAULT_NOMINAL_FILAMENT_DIA 3.0 //Enter the diameter (in mm) of the filament generally used (3.0 mm or 1.75 mm). Used for sensor reading validation
#define MEASURED_UPPER_LIMIT 3.30 //upper limit factor used for sensor reading validation in mm
#define MEASURED_LOWER_LIMIT 1.90 //lower limit factor for sensor reading validation in mm
#define MAX_MEASUREMENT_DELAY 20 //delay buffer size in bytes (1 byte = 1cm)- limits maximum measurement delay allowable (must be larger than MEASUREMENT_DELAY_CM and lower number saves RAM)
//defines used in the code
#define DEFAULT_MEASURED_FILAMENT_DIA DEFAULT_NOMINAL_FILAMENT_DIA //set measured to nominal initially
#define STANDARD_DIA 1.12837915 //The diameter of filament that has a cross sectional area of 1 square mm. This dia should be used in the slicer software settings