homing & encoders

Need some information:

are the encoders reset to 0 when machine is in "home-position" ? If not, ist there a way to do this?
Found nothing in emc-doc.

regards, Thomas

Well, i tested index-enable for mesa encoder and axis.*.index-enable.
Set all Home-Settings "0" : Home,Home_Position, Home_Offset.

There is still a "strange" behaivour of hostmot2 Stepgen:

If Homing reaches the encoder-Index the Machine wants to move back to the origin-position where i started the homing, also the Stepgen ignores Max_vel during this move back. I got a joint-follow error, pressed OK (for the error-message) then F2 to switch machine on, Stepgen accelerated again and so on... Same config but stepgen on a parport ist totally different, seems that parport stops after an error and hostmot stepgen wants to complete the move... !?

Question: How do i reset the encoder-index properly? What happens AFTER the index was reset???

regards, Thomas

Well, the diagrams are different from the table under 0.1.2 HOMING SEQUENCE.
This Table tells me that the following setup should work:

HOME = 0
HOME_POSITION = 0
HOME_SEQUENCE = 0
HOME_OFFSET = 0
HOME_SEARCH_VEL = 0
HOME_LATCH_VEL = -2
HOME_USE_INDEX = YES

Why does the machine move back to the position where the Homing started?
Index is tripped (Hal -> index--pin ist set to FALSE)

Example:
X-Positin is 300mm
Index is at 150mm
Homing starts normal and the axis moves at Latchvel down (to 0), index is tripped, machine goes at a rapid speed (beyond all Max_VEL defs in the Ini-File) back to the point where i started the home-procedure... ???

Hello, thanks for the answers,
I've tested the homing on index as described in the last 2 diagrams, but they have the same error: After the Index was hit the axis wants to move back again, always to the direction where the homing started. This does NOT happen when i use the setup with Stepgen over Parport. Rest of the Ini & Hal ist untouched. The last move is extremely FAST, i mean faster than everything defined for that machine, it seems that the Hostmot Stepgen does not even accelerate, think that it just starts stepping (causing Joint-Follow errors, same as in version before 2.3.1, no way to stop this except exiting emc and starting again)
All Home-Velocity values are set very low. Hm2 was updated to 2.3.1. Versions of HM2 did not change, right? Before the update dmsg gave me 0.15 & 0.6 Versions, same after the update.
Any ideas???

regards, Thomas

Yes, i had this problem (accelerating after Joint-Follow-Errors before installing 2.3.1), now this Problem is gone except when i do a home on index (no matter what kind of homing Index-Only / Index + Switch)

If i use just HOME-Switches everyting seems to be ok. Well, there is still an "abnormal" acceleration on the beginning of the final move (Stepgen accels for about 1/4 second too much but returns immedeatly to the programmed Velocity. To make those test i've set all home-related velocitys to 2.0.

regards, Thomas

Following my ini (just till Axis: X)

[HOSTMOT2]
DRIVER=hm2_pci
BOARD=5i20
CONFIG="firmware=hm2/5i20/SVST8_4.BIT num_encoders=4 num_pwmgens=0 num_stepgens=3"

[EMC]
MACHINE = HM2-Stepper
NML_FILE = emc.nml
#DEBUG = 0x00000003
#DEBUG = 0x00000007
DEBUG = 0

[DISPLAY]
DISPLAY = tkemc
LANG = de
POSITION_OFFSET = ABSOLUTE
POSITION_FEEDBACK = ACTUAL
MAX_FEED_OVERRIDE = 2
INTRO_GRAPHIC = emc2.gif
INTRO_TIME = 2
PROGRAM_PREFIX = //home/gtom/nc
INCREMENTS = 10mm 5mm 1mm .5mm .1mm .05mm .01mm .005mm
EDITOR = gedit
TKEMCEX = 1
WIDTH = 800
HEIGHT = 800
X = 1
Y = 1
USE_JOGWHEEL = 1

[TASK]
TASK = milltask
CYCLE_TIME = 0.010

[RS274NGC]
PARAMETER_FILE = hm2-stepper.var

[EMCMOT]
EMCMOT = motmod
COMM_TIMEOUT = 1.0
COMM_WAIT = 0.010
SERVO_PERIOD = 1000000
TRAJ_PERIOD = 10000000

[HAL]
HALFILE = hm2test.hal
#HALCMD = save neta

[TRAJ]
AXES = 3
COORDINATES = X Y Z
LINEAR_UNITS = mm
ANGULAR_UNITS = degree
CYCLE_TIME = 0.010
#CYCLE_TIME = 0.020
DEFAULT_VELOCITY = 6.00
MAX_LINEAR_VELOCITY = 8.00
POSITION_FILE = position.txt
MAX_VELOCITY = 8.0
DEFAULT_ACCELERATION = 8
MAX_ACCELERATION = 10
NO_FORCE_HOMING = 1

[AXIS_0]
TYPE = LINEAR
MAX_VELOCITY = 6.0
MAX_ACCELERATION = 8.0
STEPGEN_MAXACCEL = 8.2
SCALE = 320.0
FERROR = 1
MIN_FERROR = 0.9
MIN_LIMIT = -200.0
MAX_LIMIT = 200.0

HOME = 0
HOME_POSITION = 0
HOME_SEQUENCE = 0

## Homing with Index
HOME_OFFSET = 180
HOME_SEARCH_VEL = 4
HOME_LATCH_VEL = -4
HOME_FINAL_VEL = 4
HOME_USE_INDEX = YES
HOME_IGNORE_LIMITS = YES

DIRSETUP = 200
DIRHOLD = 200
STEPLEN = 4000
STEPSPACE = 4000

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And this is my hal (also till X-Axis)

loadrt trivkins
loadrt [EMCMOT]EMCMOT servo_period_nsec=[EMCMOT]SERVO_PERIOD num_joints=[TRAJ]AXES
#loadrt probe_parport

# hostmot2 driver
loadrt hostmot2

# load low-level driver
loadrt [HOSTMOT2](DRIVER) config=[HOSTMOT2](CONFIG)

# watchdog
setp hm2_5i20.0.watchdog.timeout_ns 10000000

# THREADS
addf hm2_5i20.0.read servo-thread
addf motion-command-handler servo-thread
addf motion-controller servo-thread
addf hm2_5i20.0.write servo-thread
addf hm2_5i20.0.pet_watchdog servo-thread

# io- spindle
net spindle-cw <= motion.spindle-forward

# io- coolant
net coolant-flood <= iocontrol.0.coolant-flood

#linear encoders
setp hm2_5i20.0.encoder.00.scale 200
setp hm2_5i20.0.encoder.00.index-enable 1
setp hm2_5i20.0.encoder.00.filter 1
setp hm2_5i20.0.encoder.01.scale 200
setp hm2_5i20.0.encoder.01.index-enable 1
setp hm2_5i20.0.encoder.01.filter 1
setp hm2_5i20.0.encoder.02.scale -200
setp hm2_5i20.0.encoder.02.index-enable 0
setp hm2_5i20.0.encoder.02.filter 1

# connect encoder index-enables for homing on index

net Xindex-enable hm2_5i20.0.encoder.00.index-enable <=> axis.0.index-enable

net Yindex-enable hm2_5i20.0.encoder.01.index-enable <=> axis.1.index-enable


#gpio
setp hm2_5i20.0.gpio.024.is_output 1
setp hm2_5i20.0.gpio.025.is_output 1
setp hm2_5i20.0.gpio.026.is_output 1
setp hm2_5i20.0.gpio.028.is_output 0
setp hm2_5i20.0.gpio.029.is_output 0

#set stepgen.2 z-direction
setp hm2_5i20.0.gpio.061.invert_output 1

# IO-> MESA
net spindle-cw => hm2_5i20.0.gpio.024.out
net coolant-flood => hm2_5i20.0.gpio.025.out
net both-home-y <= hm2_5i20.0.gpio.029.in
net both-home-x <= hm2_5i20.0.gpio.028.in


#X
# enable chain
newsig emcmot.00.enable bit
sets emcmot.00.enable FALSE
net emcmot.00.enable <= axis.0.amp-enable-out
net emcmot.00.enable => hm2_5i20.0.stepgen.00.enable
# position command and feedback
net emcmot.00.pos-cmd <= axis.0.motor-pos-cmd
net emcmot.00.pos-cmd => hm2_5i20.0.stepgen.00.position-cmd
#net motor.00.pos-fb <= hm2_5i20.0.stepgen.00.position-fb
net motor.00.pos-fb <= hm2_5i20.0.encoder.00.position
net motor.00.pos-fb => axis.0.motor-pos-fb

# homing
net both-home-x => axis.0.home-sw-in
net both-home-x => axis.0.neg-lim-sw-in
net both-home-x => axis.0.pos-lim-sw-in

# timing parameters
setp hm2_5i20.0.stepgen.00.dirsetup [AXIS_0]DIRSETUP
setp hm2_5i20.0.stepgen.00.dirhold [AXIS_0]DIRHOLD
setp hm2_5i20.0.stepgen.00.steplen [AXIS_0]STEPLEN
setp hm2_5i20.0.stepgen.00.stepspace [AXIS_0]STEPSPACE
setp hm2_5i20.0.stepgen.00.position-scale [AXIS_0]SCALE
setp hm2_5i20.0.stepgen.00.maxaccel [AXIS_0]MAX_ACCELERATION
setp hm2_5i20.0.stepgen.00.maxvel 0
setp hm2_5i20.0.stepgen.00.step_type 0
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