#linuxcnc Logs
Apr 10 2023
#linuxcnc Calendar
12:44 AM Deejay: moinsen
01:14 AM Vvega[m]: Anyone here got 7c80 Mesa board experience
01:14 AM Deejay: welcome to the black mesa transit system
01:14 AM Vvega[m]: Or even just experience using a servo as a spindle
01:14 AM * Deejay does not
01:15 AM Vvega[m]: 😦
01:16 AM Vvega[m]: I’m trying to work out if I’m outputting a pwm spindle signal , if that should go to the step input , or use the 0-10v analog input on the drive
01:19 AM XXCoder: hi, now is pretty quiet for a chat here, but no worries, it will be bit more bust later :)
01:22 AM jpa-: Vvega[m]: if you use step input, use stepgen instead of PWM
01:23 AM jpa-: PWM could be filtered and fed into 0-10V analog, which i guess is what the "analog spindle interface" on 7c80 does
01:32 AM Vvega[m]: Yes as I understand
01:32 AM Vvega[m]: I think I need to change the input in the servo to analog control as well .
01:33 AM Vvega[m]: Atm it’s wired spindle output to the analog input
01:33 AM Vvega[m]: But no movement… so that might be the issue
03:40 AM jpa-: analog signals are fortunately easy to check with multimeter, so that you know whether it is on the 7c80 side or on the servo drive side
04:38 AM Tom_L: morning
05:08 AM Vvega[m]: So sadly … I’ve moved it to analog speed mode and it’s playing up …. I think I need to turn it to a voltage output rather than a pwm
05:09 AM Vvega[m]: The output is going up and down with turning the speed up and down
05:09 AM Vvega[m]: And I have got it to speed and and slow down , but it’s erratic
05:11 AM JT-Cave: morning
05:11 AM Vvega[m]: Morning
05:11 AM Vvega[m]: I was thinking about using step gen
05:11 AM Vvega[m]: But ….. this should just work
05:20 AM andypugh_: Vvega[m]: Is there a PID in the system?
05:22 AM Vvega[m]: How do you mean …. Sorry im new to this
05:22 AM * Vvega[m] uploaded an image: (7791KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/diCPMHuPzQcKPNufYEeYRNnW/F17FB1C7-2715-4A53-BA0A-7B2C8E434305.jpg >
05:23 AM andypugh_: Yes, there is a PID, called pid.s
05:23 AM andypugh_: So you have closed-loop spindle control set up.
05:23 AM * Vvega[m] uploaded an image: (8722KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/PeZkTXycwPREMkwPGzSHaflT/92BC5EEF-E9DC-4223-8839-465CC14103C9.jpg >
05:24 AM Vvega[m]: Ahh
05:24 AM andypugh_: What are the PID setting for [SPINDLE_0] in the INI file?
05:25 AM andypugh_: It may already be set like this, but set FF0 to 1 and leave the others at zero. In that configuration the spindle speed should be stable (possibly wrong, but stable)
05:26 AM Vvega[m]: Part of the problem is I’m working from a example config
05:27 AM Vvega[m]: Because there isn’t much info on 7c80 setup
05:27 AM Vvega[m]: So I’ve got everything else working and configured now ….. but I’m having trouble understanding the spindle
05:29 AM Vvega[m]: Is part of the issue going to be …. I’ve got the encoder wired up wrong ?
05:31 AM andypugh_: It certainly could be the encoder. If you set things up as I suggestd above (Edit the spindle PID to havel all zero except FF0 = 1.0 ) that takes the encoder out of the system.
05:31 AM Vvega[m]: I’ve wired the z b and a encoder phases to the spindle encoder input
05:31 AM Vvega[m]: Ohhh I see
05:35 AM Vvega[m]: Im just checking if I can throw 24v into the spindle input …. I only have 5v atm and the drives asking for a min of 10
05:39 AM Vvega[m]: Nope 15v max …… I’ll have to see if I have something to fix that
05:41 AM * Vvega[m] uploaded an image: (3375KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/tvqbrhcssuwheVTuyLuRIDRf/B852503C-EEC6-45CB-9297-31331A0DD4CF.jpg >
05:41 AM Vvega[m]: Haha , to much odd stuff floating about
05:41 AM Vvega[m]: Umm I might not have set the encoder to differential
05:49 AM andypugh_: Vvega[m]: I have a whole drawer of DC-DC converters for this sort of job.
05:50 AM Vvega[m]: Nobody else I know gets it lol
05:51 AM andypugh_: They are so cheap now. https://www.ebay.co.uk/itm/385535005274 though yours looks like it dates from when they were expensive.
05:54 AM -!- #linuxcnc mode set to +v by ChanServ
05:58 AM Vvega[m]: I don’t even remember how much
06:07 AM Vvega[m]: Ok setting the pid values to 0 and ff0 1 ment it had no control
06:10 AM Vvega[m]: Hmmm might be a servo driver issue now
06:11 AM * Vvega[m] uploaded an image: (4178KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/KalrIejPEgqsOgNhBcGysvNt/D8818AED-61B8-4CC9-A5FE-2BF305595EF3.jpg >
06:11 AM Vvega[m]: It winds up to 3000 rpm
06:11 AM Vvega[m]: But if you stop it …. It doesn’t stop , it rotates slowly and makes and aweful noise
06:11 AM XXCoder: uh you sure it dont just brake on but still spinning?
06:28 AM Vvega[m]: No brake on the spindle motor
06:28 AM Vvega[m]: I had to ajust the 0v deadband on the motor
06:29 AM Vvega[m]: However …… im not getting a directional output from the dir pins
06:30 AM Vvega[m]: In fact the enable pins have no output too
06:32 AM * Vvega[m] uploaded an image: (7322KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/pLghbGvwMKVbVThHGBDAWJRU/FFF1FCBA-1443-4D58-97C0-ABD8C73083AF.jpg >
06:32 AM * Vvega[m] uploaded an image: (9244KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/jdHoIiugWrmVgZldDqtZVOTi/7ACC8646-36A0-471A-956F-D7C754A2FDCA.jpg >
06:38 AM * Vvega[m] uploaded an image: (7824KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/gtcnfzBOyoGMdMxEWThsqbFv/C95DBE67-BC72-44A2-9DED-C1F1CB41B12A.jpg >
06:38 AM Vvega[m]: Yeah I’ve done something wrong
06:39 AM andypugh_: Rather confusingly, dark red is off and bright yellow is on, in Halshow.
06:44 AM Vvega[m]: Yeah , the Hal is showing pin activation
06:44 AM Vvega[m]: But there isn’t any output over the pin
06:44 AM Vvega[m]: https://drewtronics.org/product/s5000led-wired-cnc-probe/
06:44 AM Vvega[m]: Also these guys seem interesting
06:47 AM Vvega[m]: Shouldn’t the spindle dir , run the same as the step dir ?
06:48 AM andypugh_: Are you connected to spindle.0.speed-out pr speed-out-abs?
06:49 AM andypugh_: Also, does the VFD need a 24V signal for direction?
06:49 AM Vvega[m]: So I have spin + to 12 v. Spin 0v to 0v and spindle output to the analog drive input
06:50 AM Vvega[m]: I#im running a 2kw servo as a spindle
06:51 AM Vvega[m]: I have the old step direction pins to the dir pins on 7c
06:51 AM andypugh_: Servo drives typically use positive voltages for forward and negative for reverse.
06:51 AM Vvega[m]: Enable is on all the time currently
06:51 AM Vvega[m]: Yes
06:52 AM Vvega[m]: But I get 0v across the spindle dir pins no matter what the hal says
06:52 AM Vvega[m]: Oh … I can set mine … 0-10v with a signal to designate direction
06:53 AM Vvega[m]: Or -10v to +10v and voltage designated direction
06:54 AM Vvega[m]: My problem atm …. Is I have no voltage output from the dir spindle pin
06:54 AM andypugh_: The TB5 Dir+ and Dir- should be treated like a switch, not a voltage output.
06:54 AM Vvega[m]: On the mesa board
06:54 AM Vvega[m]: Oh
06:54 AM Vvega[m]: So it’s just an opto output
06:55 AM andypugh_: So, if the drive needs a voltage in, then take 12V(?) to Dir+ and then Dir- to the spindle drive direction input.
06:55 AM Vvega[m]: So I’ll need to designate some input pins on the cn1 servo connector
06:56 AM andypugh_: If the drive needs the pin connecting to Gnd (fairly common) then the drive DIR goes to TB5 DIR+ and TBV DIR- goes to Gnd
06:56 AM Vvega[m]: Ok I’ll try that on the morning 11:55 pm here
06:56 AM Vvega[m]: I think my cn1 is all pulled to ground
06:57 AM Vvega[m]: Ok
06:58 AM Vvega[m]: I guess I’ll have to use enable as well
06:59 AM Vvega[m]: Thou I wanted to use position resistance to do the drawbar up lol
07:00 AM Vvega[m]: Thanks for all ya help thou , I really do appreciate it
07:01 AM Vvega[m]: I kinda wish I’d gone pc version of a mesa board …. So much documentation and examples on how people have done things
07:13 AM Vvega[m]: Also … why is there a bot after peoples names lol
07:14 AM Tom_L: some are on matrix or discord
07:14 AM Tom_L: not just irc
08:02 AM sensille: how does analog output work on mesa card? how do the fpga communicate the values to the daughter board? via sserial?
08:12 AM rmu: sensille: that depends, usually filtered and amplified PWM or PDM waveform
08:15 AM sensille: i saw that the 7i77 has 6 analog output, but only one PWM configured in the fpga
08:22 AM rmu: seems 7i77 is doing it via sserial
08:29 AM rmu: 7i48 gets PWM signals from FPGA
08:32 AM sensille: out of curiosity, how do you determine that?
08:33 AM rmu: look in manual
08:39 AM sensille: hm. the only hint i can find for the 7i77 is the section "SOFTWARE PROCESS DATA MODES". but it doesn't say anything about analog outputs, only inputs
08:39 AM sensille: do you happen to know how sserial is implemented on the 7i77 side? does it have an mcu?
08:41 AM rmu: i don't know, but i suppose there is some PIC microcontroller on the 7i77, maybe even 2
08:42 AM sensille: okay, thanks
08:44 AM pcw-home: Yes, the 7I77 has 2 DSPICs one for the digital I/O and one for analog
08:53 AM pcw-home: We chose the DSPIC because at the time it had the highest resolution PWM (1.6 GHz equivalent base frequency)
09:49 AM JT-Cave: Tom_L, when you get a chance run mesact2 on 64 bit pi and let me know what platform is reported on the machine tab
09:57 AM Tom_L: ok did you get my push?
10:00 AM bjorkintosh: https://www.youtube.com/watch?v=4N3A-eX0TOg
10:03 AM -!- #linuxcnc mode set to +v by ChanServ
10:03 AM Tom_L: JT-Cave, what platform?
10:06 AM Tom_dev: nevermind.. wrong tools
10:06 AM Tom_dev: linux-aarch64
10:55 AM sensille: is AlMg3 (AW-5754) good for dry milling? i only used 5083 so far
11:27 AM JT-Cave: Tom_L, thanks
11:40 AM roguish[m]: jsut finished cleaning up a rose bush heap..... used some cheap harbor freight welding gloves. not a scratch or poke..
11:42 AM roguish[m]: way cheaper than fancy rose pruning gloves from the local plant nursery
11:48 AM CaptHindsight[m]: for a group of people that will use micrometers as welding clamps, they sure have some elitist ideas about brands of equipment
11:50 AM bjorkintosh: hahaha
12:28 PM skunkworks[m]: Coworker is playing with a 7800x3d.. He loves it..
12:57 PM skunkworks[m]: (gamer)
01:36 PM * skunkworks[m] uploaded an image: (1075KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/dnHPfcpbDwUusTWIOfIWhZpX/PXL_20230410_183428488.jpg >
01:36 PM skunkworks[m]: Lol.. open air test bench...
01:46 PM Tom_L: only way to fly
01:53 PM Tom_L: JT-Cave, http://tom-itx.no-ip.biz:81/~webpage/cnc/JT-SHOP/mesact2/Mesact2_armhf_error.png
01:53 PM Tom_L: on armhf
01:57 PM JT-Shop: odd
01:57 PM JT-Shop: I just ran it on armhf a while ago...
01:57 PM Tom_L: fresh clone
01:59 PM Tom_L: nap time
02:00 PM JT-Shop: ok
02:10 PM Vvega[m]: Morning !! About to go reconfigure and rewire the spindle servo to suit direction change properly , found a setting that makes the spindle hold position when voltage is under threshold. Need to figure out how to get Linux cnc to accept my encoder input and hopefully order the pulley needed to connect the servo to the spindle !!
02:12 PM Vvega[m]: Then , gear down my servo encoders so I can free up some steps and processor time and the basics of the machine is done
02:29 PM * travis_farmer[m] is doing better...ish. covid is reduced to just a foggy head, headache, and gasoline runs.
02:40 PM JT-Shop: good
03:50 PM Tom_L: JT-Shop, i wound up deleting the files and cloning on arm64 and it build very quick
03:50 PM JT-Shop: hmm, I wonder what the issue was
03:51 PM Tom_L: i dunno but each version i had, the tar.xz file kept getting bigger
03:51 PM Tom_L: maybe i shouldn't keep old versions around
03:52 PM Tom_L: no idea
04:21 PM -!- #linuxcnc mode set to +v by ChanServ
04:34 PM skunkworks[m]: Vvega free up some steps and processor time?
04:37 PM Vvega[m]: Well I dunno how these boards work compared to 3D printing boards that can be an issue
04:38 PM Vvega[m]: 10k per rev x 3000 rpm …. It’s a lot of pulse generation
04:39 PM skunkworks[m]: mesa?
04:39 PM Vvega[m]: Yeah
04:39 PM Vvega[m]: 7c80
04:40 PM skunkworks[m]: not as big a deal then.. But I like analog better 😉
04:40 PM Vvega[m]: Yeah I’m already getting some warning on the axis speed
04:40 PM skunkworks[m]: Ah - ok.
04:41 PM skunkworks[m]: how has the rpi been for you?
04:41 PM Vvega[m]: So I’m gunna have to reduce resolution
04:41 PM Vvega[m]: I’ve used them for 3D printing
04:42 PM Vvega[m]: But I’m quite surprised it’s already having issues even at slower speeds
04:42 PM Vvega[m]: I think I was trying for 50mm/s
04:42 PM skunkworks[m]: maybe step space and such isn't right? that will lower your maximum step rate
04:43 PM Vvega[m]: Yeah I’m steill@learning
04:43 PM Vvega[m]: It’s moving dimensionally correct
04:43 PM Vvega[m]: 10mm is 10mm
04:43 PM skunkworks[m]: right - step space and stuff is for drive timing
04:44 PM Vvega[m]: Ahh ok yeah so lower timing = more cycles
04:44 PM Vvega[m]: In a given time period
04:44 PM rmu: skunkworks[m]: if you feel adventurous, i updated the "stupid" s-curve branch https://forum.linuxcnc.org/38-general-linuxcnc-questions/34666-c2-smooth-velocity-profile
04:45 PM Vvega[m]: My printer is doing 2250mm/s with a step duration of 0.000000031
04:45 PM skunkworks[m]: rmu: cool!
04:45 PM skunkworks[m]: Vvega sure - you need to translate that into linuxcnc terms..
04:45 PM Vvega[m]: Haha
04:46 PM Vvega[m]: That’s using clearpath servos
04:47 PM Vvega[m]: This …. Isn’t going to do anything like that
04:47 PM skunkworks[m]: Vvega (@_discord_771557407050563625:jauriarts.org) http://linuxcnc.org/docs/stable/html/man/man9/hostmot2.9.html#stepgen
04:48 PM skunkworks[m]: (u32 r/w) steplen
04:48 PM skunkworks[m]: Duration of the step signal, in nanoseconds.
04:48 PM skunkworks[m]: (u32 r/w) stepspace
04:48 PM skunkworks[m]: Minimum interval between step signals, in nanoseconds.
04:48 PM skunkworks[m]: the lower you can make them - the higher step rate you can achieve..
04:49 PM skunkworks[m]: usually in your INI
04:50 PM Vvega[m]: Yeah was just reading
04:51 PM Vvega[m]: How does that corporate to the benchmarking thing you have to do to see speed
04:51 PM Vvega[m]: Or will that not really matter because the processing is done on the fpga rather than over the parallel port
04:52 PM Vvega[m]: I know spi is fast because that’s how I communicate with my drivers o the printer
04:53 PM Vvega[m]: https://youtu.be/27AShbTkD44
04:53 PM Vvega[m]: That’s the printer
04:53 PM Vvega[m]: There is a guy moving faster now @ 3m/s
04:55 PM skunkworks[m]: Vvega what you you trying to do with linuxcnc?
04:55 PM rmu: Vvega[m]: the 7c80 is doing the step generation, servo thread on rpi is running with "only" 1kHz (usually)
04:55 PM skunkworks[m]: You are probably not going to be milling that fast...
04:55 PM Vvega[m]: Lol no I’m not
04:56 PM skunkworks[m]: rmu: refresh my memory - how do you set the 'jerk'
04:56 PM Vvega[m]: Jerk = acceleration and decel at a junction ?
04:56 PM rmu: skunkworks[m]: you don't, it is implicitly limited
04:56 PM skunkworks[m]: oh - ok
04:57 PM rmu: i will add sagemath notebooks with some calcs
04:58 PM rmu: it is using quintic bezier polynomials to interpolate from v_initial to v_target with initial and target acceleration rsp jerk = 0
04:58 PM Vvega[m]: Anyways I’m gunna order these pullys and head out to the garage
04:58 PM rmu: max acceleration is limited to not exceed acceleration
04:59 PM skunkworks[m]: ok. It has been a while since I have played with this stuff..
04:59 PM rmu: i can still trigger some acceleration excursions, but things are much better than they used to be
05:01 PM skunkworks[m]: I bought some small angular contact bearing that I thought maybe where not actually angular contact. they feel really good though pre-loaded... so - maybe
05:01 PM rmu: and it is only working on tangential velocity, so it doesn't limit jerk at line -> circle transitions
05:02 PM Vvega[m]: Generally angular contact bearings in a single row … are not preloaded at all
05:03 PM Vvega[m]: You would normally buy them as a matched pair
05:04 PM Vvega[m]: Also looking at the inner race .. one side is wider on the face than the other …. That’s probably the easiest way to tell
05:04 PM rmu: hmm. 3d_chips still very bad...
05:05 PM Vvega[m]: How do you calculate stepspace
05:08 PM andypugh_: Vvega[m]: You generally get the data from the stepper drive manual.
05:10 PM JT-Shop: I did watch Leo's last video and it was quite funny
05:18 PM skunkworks[m]: Vvega yes - I am pre-loading a pair
05:21 PM * skunkworks[m] uploaded an image: (613KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/qxqvueQMlrDqgVwkovYtklYr/PXL_20230410_222013769.jpg >
05:22 PM skunkworks[m]: They actually scay - red seals out - preload center.
05:23 PM skunkworks[m]: they are smoooooooooth...
05:24 PM Vvega[m]: How are you preloading it ?
05:24 PM skunkworks[m]: nut..
05:24 PM Vvega[m]: Is there a shoulder on the screw side
05:25 PM skunkworks[m]: yes
05:25 PM Vvega[m]: Ah yeap
05:25 PM Vvega[m]: Easy enough …. If you can feel drag you have to much preload
07:48 PM -!- #linuxcnc mode set to +v by ChanServ
08:28 PM -!- #linuxcnc mode set to +v by ChanServ
09:09 PM * Vvega[m] uploaded an image: (2178KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/vfjZFcQXPwXFgHnExJZDbpnX/IMG_7329.jpg >
09:09 PM Vvega[m]: Still working on it
09:09 PM Vvega[m]: I think I’m gunna need to rewire the cn1
09:10 PM Vvega[m]: But these English converted Manuel’s do my head in
09:12 PM * Vvega[m] uploaded an image: (4973KiB) < https://libera.ems.host/_matrix/media/v3/download/jauriarts.org/GFqVjnObGooTSmxHjQszgrNh/418881DA-0E4F-43D4-8E83-88B8D3941560.jpg >
10:28 PM CaptHindsight[m]: I have my Manuel's imported from Barcelona
11:07 PM roycroft: manuel labor can usually be found outside the home depot around here
11:24 PM -!- #linuxcnc mode set to +v by ChanServ