#garfield Logs

Nov 08 2020

#garfield Calendar

12:05 AM rue_mohr: oof, thats some itchy teeth
04:35 AM rue_bed: well, there I can check that off the list, a LM3914 based ADC
04:35 AM rue_bed: I think I came up with that on my own
04:36 AM rue_bed: but I'd like to make a frequency based one
04:36 AM rue_bed: with a fsm that co-ordinates the counter and latch
04:36 AM rue_bed: or a 4017
04:37 AM rue_bed: I suppose if you have a 556 with a gate timer and the conversion osc on it, the drift cancels out
04:37 AM rue_bed: oh no, I might not get sleep today
04:38 AM rue_bed: I have to write this down...
04:38 AM rue_bed: damnit...
07:05 AM polprog: amazing you still have notes from when you were that young
09:10 AM Tom_L: you don't forget things like that you little whipper snapper !
01:03 PM TermMoon: jumping beans!
01:03 PM polprog: rue_mohr: https://polprog.net/rozne1/ircjunk/hct14level.png
01:03 PM rue_mohr: no, just an LM3914 based ADC
01:03 PM rue_mohr: oh
01:03 PM polprog: something along the lines of that
01:04 PM rue_mohr: lets see
01:04 PM rue_mohr: hmmm, ok
01:04 PM polprog: alternatively with some diodes to make it a bit more linear
01:04 PM rue_mohr: whats the min. operating votlage of the 14
01:04 PM rue_mohr: 3?
01:05 PM polprog: i cant test it now though, desks a mess and i have tons of work from uni
01:05 PM polprog: i think 3. or 4.5
01:05 PM rue_mohr: k
01:05 PM rue_mohr: and the thresholds are a % of VCC....
01:05 PM polprog: yeah, non linear
01:06 PM rue_mohr: and the max vcc for HCT would be.... 15?
01:06 PM polprog: yeah
01:07 PM rue_mohr: so.... by playing with vcc and gnd offsets...
01:07 PM polprog: bonus points for using HC04 as a buffer amplifier
01:07 PM rue_mohr: I need to go test this vco
01:07 PM rue_mohr: I needed the pullups, and the silly LM3914 is *just* a sinking driver
01:08 PM rue_mohr: so the diode rom had to be backwards and I needed the inverters to fix it
01:08 PM rue_mohr: the headroom on Vl was *quite* small
01:08 PM rue_mohr: after the drivers and the diodes
01:09 PM TermMoon: could one of you fellows remind me of what kind of software I need for doing the Spartan stuff?
01:09 PM rue_mohr: xilinx
01:10 PM rue_mohr: er...
01:10 PM rue_mohr: Tom_L, ?
01:10 PM TermMoon: :P
01:10 PM rue_mohr: yea xilinx webpack
01:10 PM rue_mohr: you need a free key :/
01:11 PM TermMoon: free key?? ill look on thier site
01:14 PM Tom_L: spindle nearly all done
01:14 PM Tom_L: brake connected
01:14 PM Tom_L: all that's left is to tune the analog with the spindle speed
01:14 PM Tom_L: rigid tapping works etc
01:18 PM MonyMoon: https://www.xilinx.com/support/download/index.html/content/xilinx/en/downloadNav/device-models/bsdl-models/spartan-series-fpgas.html
01:18 PM MonyMoon: I'm lost
01:41 PM MonyMoon: distraction, off to debugging a server process now ;)
02:38 PM polprog: i built it
02:38 PM polprog: a hct14 6 bit ADC
02:39 PM polprog: 1 resistor 8 diodes
02:39 PM polprog: let me draw it
03:02 PM rue_mohr: yea cmon
03:02 PM rue_mohr: MonyMoon, "Web pack"
03:03 PM rue_mohr: "ise webpack"
03:03 PM TermMoon: ok
03:03 PM rue_mohr: https://www.xilinx.com/products/design-tools/ise-design-suite/ise-webpack.html
03:03 PM rue_mohr: I think
03:03 PM TermMoon: thank you!
03:03 PM rue_mohr: so I did another ADC, 16 bit binary
03:04 PM rue_mohr: using a LM556
03:07 PM Tom_L: rue_mohr, good at PID tuning?
03:12 PM rue_mohr: no I'm horrid at it
03:15 PM polprog: https://polprog.net/rozne1/ircjunk/hct14_adc/
03:15 PM polprog: supper time
03:17 PM Tom_L: when it gets into the extra terms like FF0 Ff1 Ff2 i'm lost
03:17 PM rue_mohr: !?
03:17 PM rue_mohr: its not just P I and D?
03:17 PM Tom_L: no
03:18 PM Tom_L: http://linuxcnc.org/docs/2.7/html/man/man9/pid.9.html
03:18 PM Tom_L: it works, i just want it not to overshoot
03:18 PM Tom_L: when i go from say 5000 rpm and command 500 it stops then builds up to 500
03:18 PM Tom_L: the other way around it overshoots the 5000 and settles back to it
03:19 PM rue_mohr: polprog, I should show you a super-linear triangle generator
03:19 PM rue_mohr: Tom_L, ok, thats way out then
03:19 PM polprog: you should, this is just quick and dirty :)
03:20 PM Tom_L: rue_mohr, i brought it in from the sherline motor since it was there
03:20 PM Tom_L: i just need to fix it
03:20 PM rue_mohr: polprog, the general idea is that you take two current sources, one sourcing and one sinking, put them in series, then use 2 diodes to shunt one of them out, and two diodes to connect them to a capacitor to charge/discharge
03:21 PM rue_mohr: Tom_L, the new motor already does speed control for the most part
03:21 PM Tom_L: yes but this gets the analog value to it a hellofalot closer than without it
03:21 PM rue_mohr: ok
03:22 PM Tom_L: it settles to dead on the commanded value every time
03:22 PM rue_mohr: The tuning process I know, is
03:22 PM rue_mohr: a) set I and D to zero
03:22 PM rue_mohr: b) adjust P so you get a *bit* of overshoot
03:23 PM rue_mohr: c) not sure, screw with the I and D terms somehow
03:23 PM rue_mohr: I usually go wrong on C
03:23 PM rue_mohr: but D will usually fix things on its own, I is just trouble
03:24 PM rue_mohr: ok I have to go get a test done, 10% of the course mark
03:27 PM TermMoon: HOLY tits FUCK! do I need all 8GB of this???
03:27 PM Tom_itx: setp pid.0.Pgain 1
03:27 PM Tom_itx: setp pid.0.Igain 3.5
03:27 PM Tom_itx: setp pid.0.FF0 1
03:28 PM Tom_L: there is not D term
03:28 PM Tom_L: i might bump P up a tiny bit
03:33 PM polprog: grr. gotta go back to mech
03:34 PM polprog: https://twitter.com/synx508/status/1325550609899065344?s=19
03:34 PM polprog: clever diode rom matrix for my contraption
03:34 PM polprog: now i wanna chain two hct's, and see how fast can it go
03:34 PM polprog: since it virtually has no sampling rate
03:34 PM polprog: yet
03:34 PM polprog: i could add an s&h but it doesnt need one
03:41 PM polprog: rue_mohr: hmm, i might try that
03:58 PM TermMoon is now known as MoonyMoon_t
04:14 PM rue_mohr: MoonyMoon_t, yes
04:18 PM MoonyMoon_t: balls
04:18 PM MoonyMoon_t: ok
04:18 PM MoonyMoon_t: XD
04:19 PM rue_mohr: yea, and thats not unpacked yet
04:19 PM rue_mohr: bloatware anyone?
04:19 PM MoonyMoon_t: fuck :P
04:24 PM MoonyMoon_t: Susan says COVID numbrs are too high btw
04:24 PM MoonyMoon_t: i cant visit places x'cept 4 work
04:25 PM MoonyMoon_t: >:|
04:28 PM rue_mohr: they going up again?
04:29 PM rue_mohr: we need to make a teleprescence robot!
04:29 PM rue_mohr: 3d camera and arms
04:31 PM MonyMoon: ha shure ok :P
04:35 PM rue_mohr: it will help me become accustomed to being a robot
04:35 PM rue_mohr: I can comeover by just dialing in
04:35 PM MoonyMoon_t: training
05:28 PM polprog: so looks like w are building adcs now
05:29 PM polprog: we*
05:29 PM polprog: and hey. that last video didnt cut sound out periodically and played on the web version of twatter
05:46 PM rue_mohr: yea I been using the output with out the tail, which for some reason is ok, the tail and with video with the tail appended to it are all the same settings, but dont play.
05:48 PM polprog: ok, ordered some parts that ive been short on
05:49 PM polprog: 1n4148, caps, leds, pin headers, 2n2222a, 4011, 4013, 4046, 4069, ua741, resistor pack
05:49 PM rue_mohr: :)
05:49 PM rue_mohr: from china I hope
05:50 PM polprog: no, not really. but local seller with china prices
05:50 PM polprog: i should have them on tue
05:51 PM polprog: i need a place to put the argon tube for the time being
05:51 PM polprog: i dont wanna run it with the controller jerry rigged
05:51 PM rue_mohr: :S carefull
05:51 PM polprog: because i suppose it defaults to MAXIMUM POWER
05:51 PM polprog: i have the pinout, ill have to confirm that its correct
05:52 PM polprog: then i need to find the unobtanium mating plug and cable for it.. and make up a nice control box
05:52 PM polprog: full on dexter's lab
05:52 PM polprog: after all these years
05:52 PM polprog: lol
05:52 PM rue_mohr: or a rom, you could use a rom to decode it too
05:53 PM polprog: decode that adc output
05:53 PM polprog: hmm
05:53 PM rue_mohr: yea
05:53 PM polprog: i bought.. 100pcs of 1n4148
05:53 PM rue_mohr: hahahaha
05:53 PM rue_mohr: well you COULD do that too
05:53 PM polprog: hey. 3.98 pln, thats under a dollar
05:53 PM polprog: for 100pcs
05:54 PM rue_mohr: yea, then you need to merge them...
05:54 PM rue_mohr: not sure how to do a rom for that...
05:54 PM rue_mohr: ironically, you might need inverted lines...
05:54 PM aandrew: you guys are doing some neat shit with ADCs
05:54 PM rue_mohr: hah
05:55 PM polprog: lifetime supply. ill try to make that adc use two hct14's for more bitz
05:55 PM rue_mohr: wait till you see this next video
05:55 PM rue_mohr: full 4 bits!!!
05:55 PM polprog: and try to see of CD4069 also works
05:55 PM aandrew: 3914 with diodes for BCD decode, 7414 so what looks like PWM
05:55 PM aandrew: very cool guys
05:55 PM rue_mohr: well I dont have any 74xx147!
05:55 PM polprog: it is, i cant get my head around how cool is rue's design
05:55 PM rue_mohr: OR 40147!
05:56 PM rue_mohr: I cant get my head around how, back in 1991 I nonally came up with a ADC before I knew what they were, but one with binary output and a input mux
05:56 PM rue_mohr: !
05:56 PM rue_mohr: and finite state machines!
05:56 PM polprog: how old were you then
05:57 PM polprog: https://pbs.twimg.com/media/EmR2cEjVgAAoTso?format=jpg&name=large
05:57 PM polprog: i dont know us/ca calligraphy but this looks pretty for a pretty young handwriting :P
05:57 PM rue_mohr: under 16
05:57 PM rue_mohr: by a lot
05:57 PM polprog: 10?
05:58 PM rue_mohr: heh
05:58 PM rue_mohr: older for sure
05:58 PM polprog: hmm
05:58 PM polprog: 13
05:58 PM polprog: i know bc i was 13 when i started it too
05:59 PM rue_mohr: I had NOBODY how knew what I was up to
05:59 PM polprog: at least you had radioshacks
05:59 PM rue_mohr: not really
06:00 PM polprog: my first parts were my grandfather's first. then uncle cleaned out his garage and gave me some of his junk
06:00 PM rue_mohr: all but ... 1? of the chips was from scrounging
06:00 PM rue_mohr: I think I bought a 4011 from RS
06:00 PM polprog: my greatgrandfather used to be self taught, he repaired radios
06:00 PM polprog: he passed away when i was 2 or so
06:00 PM rue_mohr: I couldn't get it to behave, and there started a hatred of CMOS
06:01 PM polprog: i dont particularly like the 4xxx series either
06:01 PM polprog: :O
06:01 PM polprog: :P *
06:01 PM rue_mohr: the pullups in TTL made them "work right"
06:01 PM rue_mohr: I hated having to connect all the pins of a cmos to *somewhere*
06:02 PM polprog: hmm loking at how sar adcs work
06:02 PM rue_mohr: Tom_L, little 4 bit adc distraction >> https://twitter.com/RueNahcMohr/status/1325588455133339650
06:02 PM polprog: i bet you could make one up with a good enough fsm, comparator and an eeprom :P
06:02 PM rue_mohr: yep
06:03 PM rue_mohr: Tom_L,this one is based on that bargraph chip, LM3914 >> https://twitter.com/RueNahcMohr/status/1325565388906614784
06:03 PM polprog: i dig these hex displays
06:03 PM rue_mohr: yea
06:03 PM rue_mohr: !
06:03 PM rue_mohr: so easy to drop in
06:04 PM polprog: theres a guy who sells them on the maket there. I didnt buy from him because i bought a whole PCB full of them on the other end, but that PCB is a full blown z80188 board so i dont wanna take them apart
06:04 PM polprog: so i guess ill buy one or two from him, loose
06:04 PM polprog: or make a vertical one based on a gal
06:04 PM polprog: or an eeprom, whatever i have more of
06:04 PM polprog: it will be bigger for sure, but cool
06:06 PM polprog: ok, back to mech
06:14 PM aandrew: I was lucky - I started doing this stuff around age 5-6 and had a dad who knew a little bit of everything but I very quickly outgrew what he knew
06:14 PM rue_mohr: :)
06:15 PM aandrew: then in grade 1 I met a friend in school who was also playing around with this stuff and who'd outgrown his dad's knowledge, and we grew together
06:15 PM rue_mohr: I'm catching up with what I knew back then
06:15 PM rue_mohr: now that I can do it
06:15 PM aandrew: taught each other C and assemly, electronics, some mechanical stuff, it was great
06:15 PM aandrew: we both had dads who had a slight hoarder mentality so there was always lots of junk to play with, and they both encouraged us to experiment
06:15 PM rue_mohr: ice
06:15 PM rue_mohr: nice
06:16 PM aandrew: I distinctly remember dad teaching me about parabolic reflectors, and using Lotus 1-2-3 to graph y=0.5x^2 for a nice wide one, then using a ruler and compass to find the focal point
06:16 PM rue_mohr: :)
06:17 PM aandrew: took a sheet of tin and bent it into the parabola by using the paper Iprinted with the graph
06:17 PM aandrew: stuck a microphone there, and I'll never ever ever forget the feeling when something theoretical became real when I could hear the dog panting like 100' away at the end of the driveway near the gate to the field
06:17 PM rue_mohr: I wonder if I should bump that ADC to 8 bits before I tear it down...
06:18 PM rue_mohr: :) hah nice
06:18 PM polprog: yeah~!
06:18 PM polprog: oh boy nice
06:18 PM polprog: i was about to ask if you used it to make a parabolic mirror and set the ants on fire
06:18 PM polprog: but the mic trick is also nice.. ;)
06:19 PM rue_mohr: I'm not sure why I needed that delay on the reset line of the counter
06:20 PM rue_mohr: the edge SHOULD have caught first
06:20 PM rue_mohr: two big exams tommorow
06:20 PM rue_mohr: I just have to not panic and I'll be ok
06:20 PM aandrew: didn't think of ants, but I also remember stringing hundreds of feet of 4-conductor telephone wire around the farmhouse and planting speakers on the ends of them, and using them as microphones to spy up in the loft in the garage
06:21 PM rue_mohr: heh
06:21 PM aandrew: you'll do great rue_mohr, this is all remedial stuff for you I'm sure -- filling in holes in your knowlege
06:21 PM rue_mohr: not even, we got up to D flipflops
06:21 PM rue_mohr: I just had to pay attention to their terminology
06:21 PM polprog: so now you feel like i did before the electronics exam
06:22 PM rue_mohr: and quirks
06:22 PM polprog: thats the worst part, when you know it but you have to remember how they specifically taught you...
06:23 PM aandrew: yeah ... when I was in grade 13 (Ontario used to have a 5th year for academics headed to university) I walked out of school halfway through final semester. the only two classes I had were Physics and Calculus, both by the same teacher who was *awesome*
06:23 PM rue_mohr: "computers that used serial shift registers for memory crashed a lot, but now we have parallel registers and things are fast and stable"
06:23 PM rue_mohr: :S
06:23 PM aandrew: I just couldn't do it. I told him, I'll be back next semester"
06:23 PM aandrew: came back next semester and I swear it was the same page in the physics text, I just said nope I can't do this anymore and walked out
06:23 PM polprog: what, do they mean that extra long intel shift register memory IC?
06:23 PM polprog: oh, that sucks
06:23 PM aandrew: I just can't do school anymore. I love to learn but the actual school part I'm done with
06:24 PM polprog: ah
06:24 PM rue_mohr: I cant test worth a damn
06:24 PM rue_mohr: I lock up and read things wrong and ugh
06:24 PM aandrew: I'm 44 now, haven't set foot in a school (as a student) since then
06:24 PM rue_mohr: lucky if I get my name down right
06:24 PM aandrew: yeah I'm not an academic. I learn by doing, and theoretical shit is fun to talk about over drinks, but I need a project to learn
06:25 PM rue_mohr: yea a target helps
06:25 PM rue_mohr: lots
06:25 PM aandrew: I helped all my friends in uni, and I can mentor people fine, but as far as actually learning in that environment... fuck that.
06:25 PM rue_mohr: I'm wondering if I want to build one of these FSM robot controllers I designed as a kid
06:26 PM rue_mohr: some of those diagrams are crazy
06:26 PM aandrew: I saw that on twitter -- is it just an FSM for something like a bounce off the walls kind of bot or something?
06:26 PM rue_mohr: but the ideas are sound
06:26 PM aandrew: it sounds like you found some old notebooks. I love going through my old shit
06:26 PM rue_mohr: no, it was for directed driving
06:26 PM rue_mohr: its my old old book
06:26 PM polprog: i should read and scan my great grandpas notebook
06:27 PM polprog: see what's in there
06:27 PM rue_mohr: I was looking for a FSM I did that used a loop that included ROM and RAM
06:27 PM aandrew: https://imgur.com/a/J1ZwSlD is what I did this afternoon
06:27 PM aandrew: had to rebuild the inner wall since I fucked up a calculation and it would never have fit
06:27 PM aandrew: so now I ahve inner and outer walls and can pour the concrete tomorrow hopefully
06:27 PM rue_mohr: I'm fascinated by the idea of an FSM that has a dynamic component
06:28 PM rue_mohr: but I dont know what I did, there is a diagram missing
06:28 PM aandrew: gotta buy probably 300lbs of rocks too, I made it too deep but I prefer to have the drainage :-)
06:28 PM rue_mohr: I'v lost quite a bit from that era
06:28 PM rue_mohr: dont forget to brace the inside really well
06:29 PM rue_mohr: you know, usually people just buy a precast box eh?
06:29 PM aandrew: polprog: I have my gradfather's steamer trunk... there was some neat stuff in there. postcards of scenery that he liked, every single pay stub he ever had, the bible from my grandmother's funeral, his old watch, dozens of keys to things that just don't exist anymore, letters that i wrote to him as a kid... I tossed everything I could manage to part with but there's still a lot and I don't want ot get
06:29 PM aandrew: rid of it but it's of no use to me
06:30 PM rue_mohr: mind the gas guys dont flip out, I think there is supposed to be 2m clearance, but maybe thats just to devices
06:30 PM aandrew: rue_mohr: yeah I have some 2x4s I'm planning on using as internal bracing although there is NOT that much concrete -- 3/4 - 1"
06:30 PM aandrew: rue_mohr: what they don't know won't hurt them
06:30 PM aandrew: once the lid is on it and dirt's over it they won't know
06:30 PM polprog: aandrew: hm, that sounds like some memories
06:31 PM rue_mohr: heh, the hidden junction box "The tape is NOT going thru!! its hitting something!!!"
06:31 PM aandrew: yeah I am kind of a sentimental guy I guess
06:32 PM rue_mohr: yard lights?
06:32 PM aandrew: no, irrigation
06:32 PM rue_mohr: ooh, not electrical then
06:32 PM aandrew: nope, well just low voltage to drive the solenoids
06:32 PM rue_mohr: whats the copper line?
06:32 PM aandrew: ohh that's just sitting there
06:32 PM aandrew: that WILL be the water source
06:33 PM rue_mohr: well
06:33 PM rue_mohr: the first adc was to prove my 1991 idea
06:33 PM aandrew: 1" coming from the main manifold in the basement, through a check valve, shut-off valve and blow out port, then down to the box in the ground
06:33 PM rue_mohr: the second was to prove last nights idea
06:34 PM rue_mohr: I cant really think of a point to these tho
06:34 PM rue_mohr: not particularily small
06:34 PM aandrew: sometimes the journey is the destination
06:35 PM rue_mohr: tho, cheaper than a 8 bit adc
06:35 PM aandrew: you do a lot of really cool shit that's just experimental
06:35 PM rue_mohr: if I needed more on a uC
06:35 PM rue_mohr: sometimes the ideas build a base
06:35 PM rue_mohr: I'm ready for my FSM challenge....
06:35 PM aandrew: gotta put some duct tape down around that 1.25" PVC so the concrete will not leak
06:35 PM rue_mohr: back then I could work out how to do anything wihthout a CPU
06:36 PM aandrew: I was considering wrapping the boxes in plastic, but figured I can take apart the inner box easily (from the inside) but that outer box is gonna be hell to get out, might just leave it to rot where it lies
06:36 PM rue_mohr: I tried to understand the point of a CPU and I'm only just recently comming back from it
06:36 PM aandrew: it's screwed together to come apart but I don't have a lot of clearance to get the drill in there
06:37 PM aandrew: might wrap that PVC in plastic though to make it easier to remove them instead of leaving them there which was my original plan
06:37 PM rue_mohr: just let the concrete set up real good before you pry at all
06:37 PM rue_mohr: any mesh in there?
06:37 PM rue_mohr: have a vibrator to get it in ok?
06:38 PM aandrew: no mesh, I do have some basic "chicken wire" type stuff I was going to slide in
06:38 PM aandrew: I was thinking of making the concrete a little wetter to get it to slide in better
06:38 PM aandrew: might end up renting a vibrator though
06:38 PM aandrew: won't be able to get a vibe in there with mesh though
06:39 PM aandrew: I wanted 1" thick concrete walls but miscalculated and gonna end up with 3/4"
06:39 PM aandrew: should be fine, it's not under any load
06:39 PM rue_mohr: just whacking the side of the form will help lots
06:40 PM aandrew: I'm good at whacking
06:41 PM aandrew: and I'm in no rush to remove the forms, I can let them sit there all winter in fact
06:41 PM rue_mohr: among the tricks I ahve seen are a drill with a eccentric weight, and a sawsall
06:41 PM aandrew: I just want to get teh damn thing poured this year
07:05 PM polprog: goodnight
07:15 PM Tom_L: rue_mohr, good stuff
07:16 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Spindle/Belt_Guard1.jpg
07:16 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Spindle/Belt_Guard2.jpg
07:16 PM Tom_L: safety safety
07:19 PM aandrew: Tom_L: nice. keeps the digits intact
07:19 PM Tom_L: and the chips out of the pullies
07:52 PM aandrew: heh
07:52 PM aandrew: "Alexa, shut off the exercise lights" "ok"
07:52 PM aandrew: "Alexa, shut off the music lights" "ok"
07:53 PM aandrew: "Alexa, relieve me of my existential dread" "... I"m sorry I can't find that book on the Kindle store"
09:00 PM rue_mohr: hmm
09:04 PM Tom_L: rue_mohr, what's up?
09:04 PM rue_mohr: cicruits
09:04 PM Tom_L: made a belt cover and sorta finished the PID tune
09:05 PM rue_mohr: and a buddy came by for stuff to fix up the new house he got
09:05 PM rue_mohr: nice
09:05 PM Tom_L: ^^
09:05 PM rue_mohr: did it tune up proper?
09:05 PM Tom_L: not too bad
09:05 PM Tom_L: i may work on it a bit more
09:05 PM Tom_L: it doesn't overshoot but on extreme changes it takes a bit to get back to the right speed
09:05 PM Tom_L: not something normally done
09:06 PM Tom_L: going from 300 rpm to 5000 and back
09:06 PM Tom_L: but it's a legitimate test
09:06 PM rue_mohr: k
09:07 PM Tom_L: and with the PID it will do 100 rpm and hold it
09:07 PM Tom_L: didn't try lower
09:07 PM rue_mohr: 100 is pretty low
09:07 PM Tom_L: yeah
09:07 PM rue_mohr: can you fly cut at 100?
09:07 PM Tom_L: i normally use 300 when touching off
09:08 PM Tom_L: i dunno, i generally don't
09:08 PM Tom_L: usually around 2000 or thereabouts
09:09 PM Tom_L: the sherline wouldn't do much more than 4000 rpm but this does 5000 with plenty of headroom
09:09 PM Tom_L: that's with the 1:1 pulley set
09:09 PM Tom_L: i could bump it up but i doubt i do
09:09 PM rue_mohr: nice
09:10 PM Tom_L: much more than that and you start asking for trouble
09:11 PM rue_mohr: yea I wonder what the bearings in the head are good for
09:11 PM Tom_L: they say 10k
09:11 PM Tom_L: sherline offers a kit for that anyway
09:12 PM Tom_L: the bearings seem real tight and free
09:14 PM Tom_L: when i made that cover and milled the edges flat, what i normally would have taken in 4-5 passes i did in 1
09:25 PM rue_mohr: nice
09:26 PM rue_mohr: does it have a load indicator of any kind?
09:26 PM rue_mohr: you might be able to program the front display to default to % load?
09:26 PM rue_mohr: I think its rpm by default
09:27 PM Tom_L: no but i did buy a chinese load meter i just don't think it will work on it due to the voltages
09:28 PM Tom_L: yeah you can change the display but i'm not sure what all it shows
09:28 PM rue_mohr: % load should be an option
09:29 PM Tom_L: duty ratio?
09:29 PM Tom_L: motor current
09:29 PM Tom_L: real speed
09:29 PM Tom_L: internal program speed
09:29 PM Tom_L: analog input
09:29 PM Tom_L: UVW phases
09:29 PM rue_mohr: they would normally have a place you put in the rated motor power, and from there, you can say % load
09:30 PM Tom_L: DC voltage of main circuit
09:30 PM Tom_L: motor current might be it?
09:30 PM rue_mohr: duty ratio sounds closest
09:30 PM Tom_L: one of those
09:30 PM rue_mohr: but so could motor current if you know your max
09:31 PM Tom_L: 1200 supposedly
09:31 PM Tom_L: drive is 1500
09:31 PM rue_mohr: er, amps...
09:31 PM Tom_L: watts
09:31 PM rue_mohr: ok
09:31 PM Tom_L: the manual doesn't say what the display shows
09:32 PM Tom_L: just current
09:32 PM Tom_L: i did set it's alarm off once
09:32 PM Tom_L: was testing 100 rpm and held the spindle too tight and it alarmed
09:33 PM Tom_L: it recovered ok after thtat
09:39 PM rue_mohr: hahah, I have to go read up how successive approximation registers work
09:39 PM rue_mohr: apparently I cant just draw one out
09:40 PM Tom_L: hehehe
09:40 PM Tom_L: school work is just so damn exacting
09:40 PM rue_mohr: no its me
09:41 PM rue_mohr: I dont feel complete if I dont make a sar adc now...
09:41 PM Tom_L: you have been doing better on your projects
09:41 PM Tom_L: smaller doable ones
09:42 PM rue_mohr: get more foundation bricks made
09:42 PM rue_mohr: these things tend to come in handy later
09:42 PM Tom_L: how's the front lights coming?
09:42 PM rue_mohr: I have them buttoned up for the winter, they are lit
09:42 PM rue_mohr: the blue is on
09:42 PM rue_mohr: its pretty bright when your eyes adjust
09:43 PM Tom_L: i thought i'd like blue when the leds came out but i think they're just too bright
09:44 PM Tom_L: hope our economy doesn't tank now
09:45 PM Tom_L: they've already said gas prices will be going up
09:47 PM rue_mohr: your gas prices have been artificialyl low for a while
09:48 PM Tom_L: oil was so cheap it went negative this year
09:49 PM Tom_L: but nobody could buy because they had no place to store it
09:49 PM Tom_L: and alot of the mainland wells aren't producing because of that
09:49 PM Tom_L: if they sit too long they go bad
09:51 PM aandrew: yeah I remember
09:51 PM aandrew: I follow the tanker trackers on twitter, which is pretty interesting on its own
09:53 PM rue_mohr: start with 8
09:53 PM rue_mohr: use the answer to change by 4
09:53 PM rue_mohr: use that answer to change by 2
09:53 PM rue_mohr: use that answer to change by 1
09:54 PM rue_mohr: there are your 4 bits
09:54 PM rue_mohr: *but*
10:00 PM rue_mohr: the DAC levels need to be offset by half a lsb value
10:06 PM Tom_L: gonna try high temp silicone for casting?
10:06 PM rue_mohr: yea, I forgot to get some on sat and the store isn't open on sun
10:06 PM Tom_L: wonder what you use for a release agent when you make the mold
10:07 PM rue_mohr: hmm
10:07 PM rue_mohr: it doens't bind well to lots of thigns
10:07 PM Tom_L: petroleum gel maybe?
10:08 PM rue_mohr: notsure
10:09 PM Tom_L: A mixture of 2 parts isopropyl alcohol and 1 part dish soap can be used in some cases to release silicone from silicone. Petroleum jelly can be used to release silicone from silicone, but it should be thinned with mineral spirits so that it can be applied in a thin layer with minimal visible brush strokes.
10:09 PM Tom_L: called that one
10:09 PM rue_mohr: I think I got some mineral spirits
10:09 PM rue_mohr: seems to keep comming up
10:09 PM Tom_L: or dip the part in oil?
10:10 PM rue_mohr: I think the hard part is getting it cast without bubbles
10:10 PM Tom_L: vacuum
10:10 PM rue_mohr: and I'm a bit nervous of pouring into it
10:10 PM rue_mohr: yea
10:10 PM rue_mohr: but you need a hell of a vac to do that
10:11 PM Tom_L: they degass alot of things that way
10:11 PM rue_mohr: ... I got the SAR alg...
10:11 PM Tom_L: nice
10:11 PM rue_mohr: yea, but this stuff is thick as calking
10:12 PM Tom_L: i know
10:12 PM rue_mohr: I made a 'guess my number'
10:13 PM rue_mohr: the last step is just a bit funny
10:15 PM rue_mohr: huh
10:15 PM rue_mohr: it fails to get 0
10:16 PM rue_mohr: oh, fix ed it
10:17 PM rue_mohr: start at 7, not 8
10:18 PM rue_mohr: void sarGuess(uint8_t target) { // for values 0-15
10:18 PM rue_mohr: uint8_t SAR = 7;
10:18 PM rue_mohr:
10:18 PM rue_mohr: if (SAR >= target) {
10:18 PM rue_mohr: SAR -= 4;
10:18 PM rue_mohr: } else {
10:18 PM rue_mohr: SAR += 4;
10:18 PM rue_mohr: }
10:18 PM rue_mohr:
10:18 PM rue_mohr: if (SAR >= target) {
10:18 PM rue_mohr: SAR -= 2;
10:18 PM rue_mohr: } else {
10:18 PM rue_mohr: SAR += 2;
10:18 PM rue_mohr: }
10:18 PM rue_mohr:
10:18 PM rue_mohr: if (SAR >= target) {
10:18 PM rue_mohr: SAR -= 1;
10:18 PM rue_mohr: } else {
10:18 PM rue_mohr: SAR += 1;
10:18 PM rue_mohr: }
10:18 PM rue_mohr:
10:18 PM rue_mohr: if (SAR < target) {
10:18 PM rue_mohr: SAR += 1;
10:18 PM rue_mohr: }
10:18 PM rue_mohr:
10:18 PM rue_mohr: printf( "%d \n", SAR);
10:18 PM rue_mohr:
10:18 PM rue_mohr: }
10:23 PM rue_mohr: so, how do I put this in a FSM ROM or GAL...
10:33 PM rue_mohr: it wasn't working on paper
10:53 PM rue_mohr: iiiinteresting
10:53 PM rue_mohr: so, I plotted out every path (this still isn't going well with my head)
10:53 PM rue_mohr: every value comes up twice
10:53 PM rue_mohr: accept the highest
10:54 PM rue_mohr: so I only need 1 extra feedback bit
11:34 PM Tom_L: ok one sewer unplugged. i'm going to bed
11:35 PM rue_mohr: !!
11:35 PM Tom_L: basement bathroom sink
11:35 PM Tom_L: full of soap gunk
11:36 PM Tom_L: dripping into the utility room
11:46 PM rue_mohr: polprog, I kinda hate to tell you this, but the 74544 is a schmitt too