static void mark_joint_homed(int joint_num) {
emcmot_joint_t *joint;
joint = &joints[joint_num];
SET_JOINT_HOMING_FLAG(joint, 0);
SET_JOINT_HOMED_FLAG(joint, 1);
SET_JOINT_AT_HOME_FLAG(joint, 1);
joint->home_state = HOME_IDLE;
}
void do_homing(void)
{
int joint_num;
emcmot_joint_t *joint;
double offset, tmp;
int home_sw_active, homing_flag;
homing_flag = 0;
if (emcmotStatus->motion_state != EMCMOT_MOTION_FREE) {
/* can't home unless in free mode */
return;
}
/* loop thru joints, treat each one individually */
for (joint_num = 0; joint_num < num_joints; joint_num++) {
/* point to joint struct */
joint = &joints[joint_num];
if (!GET_JOINT_ACTIVE_FLAG(joint)) {
/* if joint is not active, skip it */
continue;
}
home_sw_active = GET_JOINT_HOME_SWITCH_FLAG(joint);
if (joint->home_state != HOME_IDLE) {
homing_flag = 1; /* at least one joint is homing */
}
/* when an joint is homing, 'check_for_faults()' ignores its limit
switches, so that this code can do the right thing with them. Once
the homing process is finished, the 'check_for_faults()' resumes
checking */
/* homing state machine */
/* Some portions of the homing sequence can run thru two or more
states during a single servo period. This is done using
'immediate_state'. If a state transition sets it true (non-zero),
this 'do-while' will loop executing switch(home_state) immediately
to run the new state code. Otherwise, the loop will fall thru, and
switch(home_state) runs only once per servo period. Do _not_ set
'immediate_state' true unless you also change 'home_state', unless
you want an infinite loop! */
do {
immediate_state = 0;
switch (joint->home_state) {
case HOME_IDLE:
/* nothing to do */
break;
case HOME_START:
/* This state is responsible for getting the homing process
started. It doesn't actually do anything, it simply
determines what state is next */
if (joint->home_flags & HOME_IS_SHARED && home_sw_active) {
reportError(
"Cannot home while shared home switch is closed");
joint->home_state = HOME_IDLE;
break;
}
/* set flags that communicate with the rest of EMC */
SET_JOINT_HOMING_FLAG(joint, 1);
SET_JOINT_HOMED_FLAG(joint, 0);
SET_JOINT_AT_HOME_FLAG(joint, 0);
/* stop any existing motion */
joint->free_tp.enable = 0;
/* reset delay counter */
joint->home_pause_timer = 0;
/* figure out exactly what homing sequence is needed */
if (joint->home_search_vel == 0.0) {
if (joint->home_latch_vel == 0.0) {
/* both vels == 0 means home at current position */
joint->home_state = HOME_SET_SWITCH_POSITION;
immediate_state = 1;
} else if (joint->home_flags & HOME_USE_INDEX) {
/* home using index pulse only */
joint->home_state = HOME_INDEX_ONLY_START;
immediate_state = 1;
} else {
reportError("invalid homing config: non-zero LATCH_VEL needs either SEARCH_VEL or USE_INDEX");
joint->home_state = HOME_IDLE;
}
} else {
if (joint->home_latch_vel != 0.0) {
/* need to find home switch */
joint->home_state = HOME_INITIAL_SEARCH_START;
immediate_state = 1;
} else {
reportError("invalid homing config: non-zero SEARCH_VEL needs LATCH_VEL");
joint->home_state = HOME_IDLE;
}
}
break;
case HOME_INITIAL_BACKOFF_START:
/* This state is called if the homing sequence starts at a
location where the home switch is already tripped. It
starts a move away from the switch. */
/* is the joint still moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* set up a move at '-search_vel' to back off of switch */
home_start_move(joint, -joint->home_search_vel);
/* next state */
joint->home_state = HOME_INITIAL_BACKOFF_WAIT;
break;
case HOME_INITIAL_BACKOFF_WAIT:
/* This state is called while the machine is moving off of
the home switch. It terminates when the switch is cleared
successfully. If the move ends or hits a limit before it
clears the switch, the home is aborted. */
/* are we off home switch yet? */
if (! home_sw_active) {
/* yes, stop motion */
joint->free_tp.enable = 0;
/* begin initial search */
joint->home_state = HOME_INITIAL_SEARCH_START;
immediate_state = 1;
break;
}
home_do_moving_checks(joint);
break;
case HOME_INITIAL_SEARCH_START:
/* This state is responsible for starting a move toward the
home switch. This move is at 'search_vel', which can be
fairly fast, because once the switch is found another
slower move will be used to set the exact home position. */
/* is the joint already moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* make sure we aren't already on home switch */
if (home_sw_active) {
/* already on switch, need to back off it first */
joint->home_state = HOME_INITIAL_BACKOFF_START;
immediate_state = 1;
break;
}
/* set up a move at 'search_vel' to find switch */
home_start_move(joint, joint->home_search_vel);
/* next state */
joint->home_state = HOME_INITIAL_SEARCH_WAIT;
break;
case HOME_INITIAL_SEARCH_WAIT:
/* This state is called while the machine is looking for the
home switch. It terminates when the switch is found. If
the move ends or hits a limit before it finds the switch,
the home is aborted. */
/* have we hit home switch yet? */
if (home_sw_active) {
/* yes, stop motion */
joint->free_tp.enable = 0;
/* go to next step */
joint->home_state = HOME_SET_COARSE_POSITION;
immediate_state = 1;
break;
}
home_do_moving_checks(joint);
break;
case HOME_SET_COARSE_POSITION:
/* This state is called after the first time the switch is
found. At this point, we are approximately home. Although
we will do another slower pass to get the exact home
location, we reset the joint coordinates now so that screw
error comp will be appropriate for this portion of the
screw (previously we didn't know where we were at all). */
/* set the current position to 'home_offset' */
offset = joint->home_offset - joint->pos_fb;
/* this moves the internal position but does not affect the
motor position */
joint->pos_cmd += offset;
joint->pos_fb += offset;
joint->free_tp.curr_pos += offset;
joint->motor_offset -= offset;
/* The next state depends on the signs of 'search_vel' and
'latch_vel'. If they are the same, that means we must
back up, then do the final homing moving the same
direction as the initial search, on a rising edge of the
switch. If they are opposite, it means that the final
homing will take place on a falling edge as the machine
moves off of the switch. */
tmp = joint->home_search_vel * joint->home_latch_vel;
if (tmp > 0.0) {
/* search and latch vel are same direction */
joint->home_state = HOME_FINAL_BACKOFF_START;
} else {
/* search and latch vel are opposite directions */
joint->home_state = HOME_FALL_SEARCH_START;
}
immediate_state = 1;
break;
case HOME_FINAL_BACKOFF_START:
/* This state is called once the approximate location of the
switch has been found. It is responsible for starting a
move that will back off of the switch in preparation for a
final slow move that captures the exact switch location. */
/* is the joint already moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* we should still be on the switch */
if (! home_sw_active) {
reportError(
"Home switch inactive before start of backoff move");
joint->home_state = HOME_IDLE;
break;
}
/* set up a move at '-search_vel' to back off of switch */
home_start_move(joint, -joint->home_search_vel);
/* next state */
joint->home_state = HOME_FINAL_BACKOFF_WAIT;
break;
case HOME_FINAL_BACKOFF_WAIT:
/* This state is called while the machine is moving off of
the home switch after finding its approximate location.
It terminates when the switch is cleared successfully. If
the move ends or hits a limit before it clears the switch,
the home is aborted. */
/* are we off home switch yet? */
if (! home_sw_active) {
/* yes, stop motion */
joint->free_tp.enable = 0;
/* begin final search */
joint->home_state = HOME_RISE_SEARCH_START;
immediate_state = 1;
break;
}
home_do_moving_checks(joint);
break;
case HOME_RISE_SEARCH_START:
/* This state is called to start the final search for the
point where the home switch trips. It moves at
'latch_vel' and looks for a rising edge on the switch */
/* is the joint already moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* we should still be off of the switch */
if (home_sw_active) {
reportError(
"Home switch active before start of latch move");
joint->home_state = HOME_IDLE;
break;
}
/* set up a move at 'latch_vel' to locate the switch */
home_start_move(joint, joint->home_latch_vel);
/* next state */
joint->home_state = HOME_RISE_SEARCH_WAIT;
break;
case HOME_RISE_SEARCH_WAIT:
/* This state is called while the machine is moving towards
the home switch on its final, low speed pass. It
terminates when the switch is detected. If the move ends
or hits a limit before it hits the switch, the home is
aborted. */
/* have we hit the home switch yet? */
if (home_sw_active) {
/* yes, where do we go next? */
if (joint->home_flags & HOME_USE_INDEX) {
/* look for index pulse */
joint->home_state = HOME_INDEX_SEARCH_START;
immediate_state = 1;
break;
} else {
/* no index pulse, stop motion */
joint->free_tp.enable = 0;
/* go to next step */
joint->home_state = HOME_SET_SWITCH_POSITION;
immediate_state = 1;
break;
}
}
home_do_moving_checks(joint);
break;
case HOME_FALL_SEARCH_START:
/* This state is called to start the final search for the
point where the home switch releases. It moves at
'latch_vel' and looks for a falling edge on the switch */
/* is the joint already moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* we should still be on the switch */
if (!home_sw_active) {
reportError(
"Home switch inactive before start of latch move");
joint->home_state = HOME_IDLE;
break;
}
/* set up a move at 'latch_vel' to locate the switch */
home_start_move(joint, joint->home_latch_vel);
/* next state */
joint->home_state = HOME_FALL_SEARCH_WAIT;
break;
case HOME_FALL_SEARCH_WAIT:
/* This state is called while the machine is moving away from
the home switch on its final, low speed pass. It
terminates when the switch is cleared. If the move ends or
hits a limit before it clears the switch, the home is
aborted. */
/* have we cleared the home switch yet? */
if (!home_sw_active) {
/* yes, where do we go next? */
if (joint->home_flags & HOME_USE_INDEX) {
/* look for index pulse */
joint->home_state = HOME_INDEX_SEARCH_START;
immediate_state = 1;
break;
} else {
/* no index pulse, stop motion */
joint->free_tp.enable = 0;
/* go to next step */
joint->home_state = HOME_SET_SWITCH_POSITION;
immediate_state = 1;
break;
}
}
home_do_moving_checks(joint);
break;
case HOME_SET_SWITCH_POSITION:
/* This state is called when the machine has determined the
switch position as accurately as possible. It sets the
current joint position to 'home_offset', which is the
location of the home switch in joint coordinates. */
/* set the current position to 'home_offset' */
offset = joint->home_offset - joint->pos_fb;
/* this moves the internal position but does not affect the
motor position */
joint->pos_cmd += offset;
joint->pos_fb += offset;
joint->free_tp.curr_pos += offset;
joint->motor_offset -= offset;
/* next state */
joint->home_state = HOME_FINAL_MOVE_START;
immediate_state = 1;
break;
case HOME_INDEX_ONLY_START:
/* This state is used if the machine has been pre-positioned
near the home position, and simply needs to find the
next index pulse. It starts a move at latch_vel, and
sets index-enable, which tells the encoder driver to
reset its counter to zero and clear the enable when the
next index pulse arrives. */
/* is the joint already moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* Although we don't know the exact home position yet, we
we reset the joint coordinates now so that screw error
comp will be appropriate for this portion of the screw
(previously we didn't know where we were at all). */
/* set the current position to 'home_offset' */
offset = joint->home_offset - joint->pos_fb;
/* this moves the internal position but does not affect the
motor position */
joint->pos_cmd += offset;
joint->pos_fb += offset;
joint->free_tp.curr_pos += offset;
joint->motor_offset -= offset;
/* set the index enable */
joint->index_enable = 1;
/* set up a move at 'latch_vel' to find the index pulse */
home_start_move(joint, joint->home_latch_vel);
/* next state */
joint->home_state = HOME_INDEX_SEARCH_WAIT;
break;
case HOME_INDEX_SEARCH_START:
/* This state is called after the machine has made a low
speed pass to determine the limit switch location. It
sets index-enable, which tells the encoder driver to
reset its counter to zero and clear the enable when the
next index pulse arrives. */
/* set the index enable */
joint->index_enable = 1;
/* and move right into the waiting state */
joint->home_state = HOME_INDEX_SEARCH_WAIT;
immediate_state = 1;
home_do_moving_checks(joint);
break;
case HOME_INDEX_SEARCH_WAIT:
/* This state is called after the machine has found the
home switch and "armed" the encoder counter to reset on
the next index pulse. It continues at low speed until
an index pulse is detected, at which point it sets the
final home position. If the move ends or hits a limit
before an index pulse occurs, the home is aborted. */
/* has an index pulse arrived yet? encoder driver clears
enable when it does */
if ( joint->index_enable == 0 ) {
/* yes, stop motion */
joint->free_tp.enable = 0;
/* go to next step */
joint->home_state = HOME_SET_INDEX_POSITION;
immediate_state = 1;
break;
}
home_do_moving_checks(joint);
break;
case HOME_SET_INDEX_POSITION:
/* This state is called when the encoder has been reset at
the index pulse position. It sets the current joint
position to 'home_offset', which is the location of the
index pulse in joint coordinates. */
/* set the current position to 'home_offset' */
joint->motor_offset = -joint->home_offset;
joint->pos_fb = joint->motor_pos_fb -
(joint->backlash_filt + joint->motor_offset);
joint->pos_cmd = joint->pos_fb;
joint->free_tp.curr_pos = joint->pos_fb;
/* next state */
joint->home_state = HOME_FINAL_MOVE_START;
immediate_state = 1;
break;
case HOME_FINAL_MOVE_START:
/* This state is called once the joint coordinate system is
set properly. It moves to the actual 'home' position,
which is not neccessarily the position of the home switch
or index pulse. */
/* is the joint already moving? */
if (joint->free_tp.active) {
/* yes, reset delay, wait until joint stops */
joint->home_pause_timer = 0;
break;
}
/* has delay timed out? */
if (joint->home_pause_timer < (HOME_DELAY * servo_freq)) {
/* no, update timer and wait some more */
joint->home_pause_timer++;
break;
}
joint->home_pause_timer = 0;
/* plan a move to home position */
joint->free_tp.pos_cmd = joint->home;
/* if home_vel is set (>0) then we use that, otherwise we rapid there */
if (joint->home_final_vel > 0) {
joint->free_tp.max_vel = fabs(joint->home_final_vel);
/* clamp on max vel for this joint */
if (joint->free_tp.max_vel > joint->vel_limit)
joint->free_tp.max_vel = joint->vel_limit;
} else {
joint->free_tp.max_vel = joint->vel_limit;
}
/* start the move */
joint->free_tp.enable = 1;
joint->home_state = HOME_FINAL_MOVE_WAIT;
break;
case HOME_FINAL_MOVE_WAIT:
/* This state is called while the machine makes its final
move to the home position. It terminates when the machine
arrives at the final location. If the move hits a limit
before it arrives, the home is aborted. */
/* have we arrived (and stopped) at home? */
if (!joint->free_tp.active) {
/* yes, stop motion */
joint->free_tp.enable = 0;
/* we're finally done */
joint->home_state = HOME_FINISHED;
immediate_state = 1;
break;
}
if (joint->on_pos_limit || joint->on_neg_limit) {
/* on limit, check to see if we should trip */
if (!(joint->home_flags & HOME_IGNORE_LIMITS)) {
/* not ignoring limits, time to quit */
reportError("hit limit in home state %d",
joint->home_state);
joint->home_state = HOME_ABORT;
immediate_state = 1;
break;
}
}
break;
case HOME_FINISHED:
SET_JOINT_HOMING_FLAG(joint, 0);
SET_JOINT_HOMED_FLAG(joint, 1);
SET_JOINT_AT_HOME_FLAG(joint, 1);
joint->home_state = HOME_IDLE;
immediate_state = 1;
break;
case HOME_ABORT:
SET_JOINT_HOMING_FLAG(joint, 0);
SET_JOINT_HOMED_FLAG(joint, 0);
SET_JOINT_AT_HOME_FLAG(joint, 0);
joint->free_tp.enable = 0;
joint->home_state = HOME_IDLE;
joint->index_enable = 0;
immediate_state = 1;
break;
default:
/* should never get here */
reportError("unknown state '%d' during homing",
joint->home_state);
joint->home_state = EMCMOT_ABORT;
immediate_state = 1;
break;
} /* end of switch(joint->home_state) */
} while (immediate_state);
} /* end of loop through all joints */
if ( homing_flag ) {
/* at least one joint is homing, set global flag */
emcmotStatus->homing_active = 1;
} else {
/* is a homing sequence in progress? */
if (emcmotStatus->homingSequenceState == HOME_SEQUENCE_IDLE) {
/* no, single joint only, we're done */
emcmotStatus->homing_active = 0;
}
}
}
