Writing parameters

To write a parameter, send an F22 P V command, where P is the parameter number and V is the parameter value.

Reading parameters

To read parameters, use one of the following two commands.

Action	Command	Parameter Number
Report all parameters	F20
Read parameter	F21	P

The firmware will respond in the format R21 P V, where P is the parameter number and V is the parameter value.

The firmware uses the following parameters, as found in the code repository at src/ParameterList.h.

ID	Name	Description
0	`PARAM_VERSION`	Version number of the parameter set
1	`PARAM_TEST`	Used for diagnostics
2	`PARAM_CONFIG_OK`	Set when the firmware is sufficiently configured

ID	Name	Description
4	`PARAM_E_STOP_ON_MOV_ERR`	Determines wether or not the firmware should emergency stop upon movement error
5	`PARAM_MOV_NR_RETRY`	Number of times to retry a movement before stopping with error
11 12 13	`MOVEMENT_TIMEOUT_X` `MOVEMENT_TIMEOUT_Y` `MOVEMENT_TIMEOUT_Z`	Time in seconds before a movement along an axis times out and stops with error

ID	Name	Description
15 16 17	`MOVEMENT_KEEP_ACTIVE_X` `MOVEMENT_KEEP_ACTIVE_Y` `MOVEMENT_KEEP_ACTIVE_Z`	Determines if motors should remain powered when idle
31 32 33	`MOVEMENT_INVERT_MOTOR_X` `MOVEMENT_INVERT_MOTOR_Y` `MOVEMENT_INVERT_MOTOR_Z`	Reverses the direction a motor spins when moving in both the positive and negative directions
36	`MOVEMENT_SECONDARY_MOTOR_X`	Enables the use of a second X-axis motor
37	`MOVEMENT_SECONDARY_MOTOR_INVERT_X`	Inverts the rotation of the second X-axis motor
51 52 53	`MOVEMENT_HOME_UP_X` `MOVEMENT_HOME_UP_Y` `MOVEMENT_HOME_UP_Z`	Determines which direction the bot must move to reach the home (zero) position
55 56 57	`MOVEMENT_STEP_PER_MM_X` `MOVEMENT_STEP_PER_MM_Y` `MOVEMENT_STEP_PER_MM_Z`	Determines the steps/mm scaling factor

ID	Name	Description
41 42 43	`MOVEMENT_STEPS_ACC_DEC_X` `MOVEMENT_STEPS_ACC_DEC_Y` `MOVEMENT_STEPS_ACC_DEC_Z`	Number of steps used to accelerate along an axis
61 62 63	`MOVEMENT_MIN_SPD_X` `MOVEMENT_MIN_SPD_Y` `MOVEMENT_MIN_SPD_Z`	Minimum speed in steps/second
71 72 73	`MOVEMENT_MAX_SPD_X` `MOVEMENT_MAX_SPD_Y` `MOVEMENT_MAX_SPD_Z`	Maximum speed in steps/second
65 66 67	`MOVEMENT_HOME_SPEED_X` `MOVEMENT_HOME_SPEED_Y` `MOVEMENT_HOME_SPEED_Z`	Homing and calibrating speed in steps/second

ID	Name	Description
25 26 27	`MOVEMENT_ENABLE_ENDPOINTS_X` `MOVEMENT_ENABLE_ENDPOINTS_Y` `MOVEMENT_ENABLE_ENDPOINTS_Z`	Enables the use of endstop hardware such as limit switches
21 22 23	`MOVEMENT_INVERT_ENDPOINTS_X` `MOVEMENT_INVERT_ENDPOINTS_Y` `MOVEMENT_INVERT_ENDPOINTS_Z`	Inverts which endstop represents the maximum and minimum locations along an axis
75 76 77	`MOVEMENT_INVERT_2_ENDPOINTS_X` `MOVEMENT_INVERT_2_ENDPOINTS_Y` `MOVEMENT_INVERT_2_ENDPOINTS_Z`	Changes the type of limit switch being used from NO to NC
45 46 47	`MOVEMENT_STOP_AT_HOME_X` `MOVEMENT_STOP_AT_HOME_Y` `MOVEMENT_STOP_AT_HOME_Z`	Determines if the bot is allowed to move past the minimum/home (zero) position
145 146 147	`MOVEMENT_STOP_AT_MAX_X` `MOVEMENT_STOP_AT_MAX_Y` `MOVEMENT_STOP_AT_MAX_Z`	Determines if the bot is allowed to move past the maximum position
141 142 143	`MOVEMENT_AXIS_NR_STEPS_X` `MOVEMENT_AXIS_NR_STEPS_Y` `MOVEMENT_AXIS_NR_STEPS_Z`	Size of an axis in steps (lower byte)
151 152 153	`MOVEMENT_AXIS_NR_STEPS_H_X` `MOVEMENT_AXIS_NR_STEPS_H_Y` `MOVEMENT_AXIS_NR_STEPS_H_Z`	Size of an axis in steps (higher byte)
161 162 163	`MOVEMENT_CALIBRATION_RETRY_X` `MOVEMENT_CALIBRATION_RETRY_Y` `MOVEMENT_CALIBRATION_RETRY_Z`	Number of calibration attempts
171 172 173	`MOVEMENT_CALIBRATION_DEADZONE_X` `MOVEMENT_CALIBRATION_DEADZONE_Y` `MOVEMENT_CALIBRATION_DEADZONE_Z`	Calibration retry grouping distance

ID	Name	Description
81 82 83	`MOVEMENT_MOTOR_CURRENT_X` `MOVEMENT_MOTOR_CURRENT_Y` `MOVEMENT_MOTOR_CURRENT_Z`	Sets the current in milliamps
85 86 87	`MOVEMENT_STALL_SENSITIVITY_X` `MOVEMENT_STALL_SENSITIVITY_Y` `MOVEMENT_STALL_SENSITIVITY_Z`	Sets the amount of back emf required to trigger a stall
91 92 93	`MOVEMENT_MICROSTEPS_X` `MOVEMENT_MICROSTEPS_Y` `MOVEMENT_MICROSTEPS_Z`	Sets the number of microsteps per step
165 166 167	`MOVEMENT_AXIS_STEALTH_X` `MOVEMENT_AXIS_STEALTH_Y` `MOVEMENT_AXIS_STEALTH_Z`	Enables quiet motor mode

ID	Name	Description
101 102 103	`ENCODER_ENABLED_X` `ENCODER_ENABLED_Y` `ENCODER_ENABLED_Z`	Enables the use of rotary encoders
105 106 107	`ENCODER_TYPE_X` `ENCODER_TYPE_Y` `ENCODER_TYPE_Z`	Sets the type of encoder being used (single ended or differential)
111 112 113	`ENCODER_MISSED_STEPS_MAX_X` `ENCODER_MISSED_STEPS_MAX_Y` `ENCODER_MISSED_STEPS_MAX_Z`	Sets the maximum number of steps an encoder can deviate from the expected count before determining a stall has occurred
115 116 117	`ENCODER_SCALING_X` `ENCODER_SCALING_Y` `ENCODER_SCALING_Z`	Determines the scaling factor between encoder steps and motor steps
121 122 123	`ENCODER_MISSED_STEPS_DECAY_X` `ENCODER_MISSED_STEPS_DECAY_Y` `ENCODER_MISSED_STEPS_DECAY_Z`	Sets the amount the missed encoder step count should decrease by with each recorded step
125 126 127	`ENCODER_USE_FOR_POS_X` `ENCODER_USE_FOR_POS_Y` `ENCODER_USE_FOR_POS_Z`	Determines if the controller should continue moving based on the position as reported by the encoders
131 132 133	`ENCODER_INVERT_X` `ENCODER_INVERT_Y` `ENCODER_INVERT_Z`	Reverses the direction the encoder must rotate to count in each direction

ID	Name	Description
201 202 203	`PIN_GUARD_1_PIN_NR` `PIN_GUARD_1_TIME_OUT` `PIN_GUARD_1_ACTIVE_STATE`	Pin guard 1 pin number, timeout (in seconds), and active state (low or high)
205 206 207	`PIN_GUARD_2_PIN_NR` `PIN_GUARD_2_TIME_OUT` `PIN_GUARD_2_ACTIVE_STATE`	Pin guard 2 pin number, timeout (in seconds), and active state (low or high)
211 212 213	`PIN_GUARD_3_PIN_NR` `PIN_GUARD_3_TIME_OUT` `PIN_GUARD_3_ACTIVE_STATE`	Pin guard 3 pin number, timeout (in seconds), and active state (low or high)
215 216 217	`PIN_GUARD_4_PIN_NR` `PIN_GUARD_4_TIME_OUT` `PIN_GUARD_4_ACTIVE_STATE`	Pin guard 4 pin number, timeout (in seconds), and active state (low or high)
221 222 223	`PIN_GUARD_5_PIN_NR` `PIN_GUARD_5_TIME_OUT` `PIN_GUARD_5_ACTIVE_STATE`	Pin guard 5 pin number, timeout (in seconds), and active state (low or high)

The following parameters are no longer used, though support for them may still remain in the firmware.

ID	Name	Description
3	`PARAM_USE_EEPROM`
18 19 20	`MOVEMENT_HOME_AT_BOOT_X` `MOVEMENT_HOME_AT_BOOT_Y` `MOVEMENT_HOME_AT_BOOT_Z`	Deprecated