#garfield Logs
Jul 10 2020
#garfield Calendar
07:44 AM Tom_L: power back on
07:50 AM Tom_L: so rue_mohr, how did it fit?
07:50 AM Tom_L: presumably just like yours since it's the same model
08:47 AM rue_mohr: wanted the traces around the inside
08:48 AM rue_mohr: so it will work as a module within the footprint
08:48 AM rue_mohr: freaking dcma again?
09:37 AM polprog: hmm
09:38 AM polprog: im measuring rise time and propagation delay of the 327 337 pair
09:38 AM polprog: ill see if i have other complimentary bjts
09:38 AM polprog: right now looks good. sped it up with caps
09:49 AM polprog: huh. 547/557 is way slower
09:49 AM polprog: propagation delay 240ns instead of 50ns
09:50 AM polprog: rise/fall 34ns/15ns, while the bc327/337 has 32/10
10:09 AM polprog: rue_mohr: what is the cap divider for?
10:44 AM polprog: hmm, still getting weird readings
10:56 AM polprog: hmm
10:56 AM polprog: no, these make sense.. adding 4r7 in series makes it a bad reading
10:56 AM polprog: could it be that the big old caps from the crap bag are all okay
10:56 AM polprog: hmm
11:03 AM polprog: oooh theres bad one <3
11:08 AM polprog: hmm no
11:08 AM polprog: still getting weird stuff
11:26 AM aandrew: woo
11:27 AM aandrew: got the ITM output spewing
11:27 AM aandrew: 6MHz multiplexed data stream on SWO, and orbuculum is the shit
11:27 AM aandrew: I demand anyone who's using Cortex-M devices stop what you're doing and learn how to use this insanely useful tool
11:27 AM aandrew: right away
11:28 AM aandrew: I mean look at this:
11:35 AM aandrew: 65.75% 54557 HAL_ADC_PollForConversion
11:35 AM aandrew: 23.68% 19656 HAL_GetTick
11:35 AM aandrew: 2.67% 2216 uwait
11:35 AM aandrew: 1.70% 1417 HAL_ADC_Start
11:35 AM aandrew: 1.46% 1213 scanKeyISR
11:35 AM aandrew: 0.99% 828 calcMIDITick
11:35 AM aandrew: 0.41% 342 HAL_TIM_PeriodElapsedCallback
11:35 AM aandrew: 0.38% 323 encoder_poll
11:36 AM aandrew: 0.32% 273 ADC1_get_value
11:36 AM aandrew: 0.30% 255 HAL_TIM_IRQHandler
11:36 AM aandrew: 0.28% 240 LEDfromKey
11:36 AM aandrew: 0.27% 229 ADC1_start_conversion
11:36 AM aandrew: 0.22% 189 keyscan_shift
11:36 AM aandrew: 0.16% 140 TIM1_UP_TIM10_IRQHandler
11:36 AM aandrew: 0.16% 137 HAL_ADC_GetValue
11:36 AM aandrew: 0.15% 126 setMBCState
11:36 AM aandrew: 0.13% 114 processMidiMessage
11:36 AM aandrew: 0.10% 87 HAL_GPIO_ReadPin
11:36 AM aandrew: -----------------
11:36 AM aandrew: 99.13% 82342 of 82973 Samples
11:36 AM aandrew: that is literally just connecting the debugger and running a few commands -- that's a live stream of where the CPU is spending its time
11:53 AM polprog: neat
12:02 PM aandrew: it's beyond neat
12:02 PM aandrew: this is like the time I discovered tacky flux
12:02 PM aandrew: this is game changing
02:27 PM rue_mohr: polprog, the capacitor divider turns the circuit into a bipolar drive so that the average voltage across the capacitor is zero
02:27 PM rue_mohr: polprog, show me some waveforms, make sure you have that cap divider in there
02:32 PM polprog: let me rebuild it quickly
02:33 PM polprog: later on i added the cap divider but i got waveforms nowhere near yours
02:53 PM polprog: https://polprog.net/rozne1/ircjunk/various/captest1.jpg
02:54 PM polprog: https://polprog.net/rozne1/ircjunk/various/captest_print1.png
02:54 PM polprog: rue_mohr:
02:54 PM rue_mohr: wtf
02:55 PM rue_mohr: it looks like that cap is a complete fail
02:55 PM polprog: push-pull output, via resistor, ground connected in between caps
02:55 PM rue_mohr: show me with your cap-clip leads shorted
02:55 PM rue_mohr: yea
02:55 PM rue_mohr: like the leads by the way
02:55 PM polprog: they are useful
02:56 PM polprog: https://polprog.net/rozne1/ircjunk/various/captest_zero.png
02:56 PM polprog: unless the 22uf caps i used for the bridge are shite
02:56 PM rue_mohr: ok
02:57 PM rue_mohr: move trigger down till its between the peaks with the leads shorted
02:57 PM rue_mohr: use AC coupling on the scope
02:57 PM rue_mohr: and bump the sweep up a notch
02:57 PM polprog: the square wfm, ok
02:57 PM rue_mohr: yea
02:58 PM rue_mohr: thats the resistance of the leads
02:58 PM rue_mohr: so, thats your reference perfect cap
02:58 PM rue_mohr: now compare against a test capacitor
02:58 PM polprog: gonna be difficult. the ringing is crazy
02:58 PM polprog: sec
02:58 PM rue_mohr: yea, its pretty messy, which is off
02:58 PM rue_mohr: odd
02:59 PM rue_mohr: :) I have to go back to work
02:59 PM rue_mohr: watch the vertical shift amplitude |
03:00 PM rue_mohr: its also helpfull to put the leads across a 1R resistor to get an idea of scale
03:00 PM rue_mohr: iirc I was using 50mv/div
03:00 PM polprog: got it, pulse trig
03:00 PM polprog: got a brown-orng-gold resistor here
03:00 PM polprog: 1R3
03:01 PM rue_mohr: yup
03:01 PM rue_mohr: scale from there
03:01 PM rue_mohr: you will see a difference in the voltages of caps
03:01 PM rue_mohr: so the slip on a 10uF 6.3V will be less than a 10uF 250V
03:02 PM rue_mohr: (250V has more esr)
03:02 PM polprog: let me grab the crapbag of pulled caps
03:02 PM rue_mohr: nevermind slope
03:02 PM rue_mohr: you want to know the slip
03:02 PM rue_mohr: bbl!
03:02 PM polprog: slip is the "eye pattern" height?
03:06 PM polprog: ok. it works good
03:47 PM polprog: ill have to solder it, it's flimsy on the breadboard
03:48 PM polprog: i ordered some goodies, incl 2 rasterboards
03:48 PM polprog: ordered some CD4520 ICs and some persulfate
03:48 PM polprog: and what supposedly is theromotransfer paper
04:03 PM Tom_L: blue?
04:03 PM polprog: yellow
04:03 PM Tom_L: i got a bunch of blue you can have
04:03 PM polprog: https://allegro.pl/oferta/papier-termo-transferowy-a4-do-plytek-x5szt-8007543879
04:03 PM Tom_L: doesn't work as good as photo paper
04:03 PM polprog: no point in sending just paper
04:04 PM polprog: we should make a travelling parcel when we work out who want to give away what
05:36 PM polprog: goodnight
06:53 PM rue_mohr: back from work
06:53 PM rue_mohr: polprog, no, arg
06:53 PM rue_mohr: slip is the immediate vertical shift
06:53 PM rue_mohr: its not slope, its 90 degrees straight up
06:53 PM rue_mohr: | <-- thats slip
06:53 PM rue_mohr: / <-- thats just charge
06:53 PM rue_mohr: \ <-- thats discharge
06:54 PM rue_mohr: OMG I still have the photopaper for toner transfers
07:15 PM Tom_L: rue_mohr,
07:15 PM Tom_L: i didn't get if that part fit or not
07:15 PM rue_mohr: the split arg
07:15 PM rue_mohr: yea it fit perfectly
07:16 PM Tom_L: really?
07:16 PM Tom_L: kinda surprised
07:16 PM rue_mohr: <rue_mohr> http://ruemohr.org/~ircjunk/tempimage/p1160549.jpg
07:16 PM rue_mohr: <rue_mohr> http://ruemohr.org/~ircjunk/tempimage/p1160550.jpg
07:16 PM rue_mohr: <rue_mohr> http://ruemohr.org/~ircjunk/tempimage/p1160551.jpg
07:16 PM rue_mohr: heym is your paypal still goin?
07:17 PM Tom_L: i've no idea
07:17 PM rue_mohr: the owner of the saw gave me some coffee money for ya
07:17 PM Tom_L: i don't drink coffee so keep it
07:17 PM rue_mohr: use it for a bit or postage or something
07:17 PM Tom_L: just knowing it worked is good enough
07:18 PM rue_mohr: but
07:19 PM Tom_L: did you tell him that part came all the way from merika?
07:19 PM rue_mohr: I said from the states
07:19 PM rue_mohr: he was really impressed
07:19 PM rue_mohr: me and him tried to find that part
07:19 PM rue_mohr: there isn't even a referece to it
07:19 PM Tom_L: well now he has a spare
07:20 PM rue_mohr: yep, I carefully taped it into the box for him
07:20 PM rue_mohr: its still in the block
07:20 PM Tom_L: i figured that way they wouldn't get lost on the way
07:20 PM rue_mohr: what shape were the flues like on the bit you used for that?
07:20 PM Tom_L: just normal cutters
07:20 PM rue_mohr: straight or spiral
07:21 PM Tom_L: spiral
07:21 PM Tom_L: not high helix, just normal
07:21 PM rue_mohr: hmm
07:22 PM Tom_L: http://ruemohr.org/~ircjunk/tempimage/p1160551.jpg
07:22 PM Tom_L: unaproved OSHA foot wear
07:23 PM rue_mohr: heh
07:23 PM Tom_L: what did you reference the dwg from if there wasn't one
07:23 PM rue_mohr: bosch PS50 if you want to try listing some on ebay
07:23 PM Tom_L: naw
07:23 PM rue_mohr: I measured
07:24 PM rue_mohr: playing with drill bits to get radii and calipers
07:24 PM Tom_L: i picked up a set of radius gauges a while back
07:25 PM rue_mohr: I have a big one
07:25 PM rue_mohr: 3d printed
07:25 PM Tom_L: 1/64" increments
07:25 PM Tom_L: i think
07:25 PM rue_mohr: goes down to 4mm I think
07:25 PM Tom_L: 1/2" down to 1/64" iirc
07:25 PM rue_mohr: nice
07:25 PM rue_mohr: as rods or rounded squares?
07:26 PM Tom_L: and a set of imperial/metric therad gauges
07:26 PM rue_mohr: thats handy
07:26 PM Tom_L: https://www.ebay.com/itm/New-Fractional-Radius-Gage-Set-1-64-1-2-Gages-Gauge-25-PC/153526888063?hash=item23beea667f:g:nxkAAOSw4x5dAxAI
07:27 PM Tom_L: looks like the very one
07:27 PM Tom_L: but i got it local
07:27 PM rue_mohr: oh curious
07:27 PM rue_mohr: hahah
07:28 PM rue_mohr: oh no, I opened an ebay link
07:28 PM rue_mohr: their going to hound me to buy that for 3 months now
07:28 PM Tom_L: those and the thread gauges are pretty handy
07:29 PM Tom_L: https://www.ebay.com/itm/4P-Screw-Thread-Pitch-Cutting-Gauge-Tool-Set-Centre-Gage-55-60-Inch-Metric/323695385629?hash=item4b5dbf9c1d:g:k3kAAOSw~M1ZlqYZ
07:29 PM Tom_L: click that and make it 6 mo
07:29 PM rue_mohr: I got 3
07:29 PM rue_mohr: metric imperial and wootworth
07:30 PM Tom_L: nobody uses wentworth anymore
07:30 PM Tom_L: old old british standard
07:30 PM Tom_L: way back when, i bought a couple wentworth wrenches
07:31 PM rue_mohr: yea, but I got it!
07:32 PM Tom_L: i wonder why yours didn't fit now
07:32 PM rue_mohr: me too
07:33 PM Tom_L: maybe it was warm enough to melt it as it cut
07:59 PM zhanx: Cooled down to 100f outside
09:37 PM Tom_L: zhanx, workin on any projects yet?
09:45 PM zhanx: Electrical wiring
09:46 PM zhanx: Adding in a new 70 amp service box to the 50x 25
09:46 PM zhanx: 30a 220v for the weld. 4 outlets
09:47 PM zhanx: 20a x 2 for outlets
09:47 PM zhanx: And 2 10 amp circuits for lights
09:48 PM zhanx: Tom_l how is that?
09:48 PM Tom_L: do you use thinner wire for lights than outlets?
09:48 PM Tom_L: 14 over 12
09:49 PM zhanx: 14 over 12 yes
09:49 PM Tom_L: it used to be legal.. dunno if it still is but i ran 12 on everything
09:49 PM zhanx: I am running 14 cause it was on sale
09:49 PM zhanx: Honest
09:50 PM Tom_L: i'm sure it's fine, i just had lots of 12 when i did my basement so that's what i used
09:50 PM zhanx: My buddy was like wait you have a 70A box but 90 on breakers
09:51 PM Tom_L: kinda surprised it's not 100A
09:51 PM zhanx: I was like not like I can run the welder and every power tool at once
09:51 PM Tom_L: most are either 100 or 200 depending on the size of the house
09:51 PM zhanx: The house is 200
09:51 PM Tom_L: i ran 6 on a 50? A to the garage
09:51 PM zhanx: This is the pole barn thing
09:52 PM Tom_L: i've never had an issue with it
09:52 PM Tom_L: 220v compressor, welder etc
09:52 PM zhanx: The wiring will handle it . And I know the box will be fine etc
09:53 PM zhanx: I am cheating
09:53 PM zhanx: 14-3 for the outlets
09:53 PM zhanx: Every other one on other leg for the breaker
09:54 PM Tom_L: i did that on the basement too
09:54 PM zhanx: Makes it simple for the wiring really
09:55 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/house/7.jpg
09:55 PM Tom_L: i had it dug out under the house
09:56 PM zhanx: Looks like a mess
09:56 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/house/1.jpg
09:56 PM Tom_L: tore off the whole back of that shorter house part and ran it all the way across when it was done
09:57 PM Tom_L: gained an upstairs closet with that and stairs
09:57 PM zhanx: Yes I remember that from the garden pics
09:57 PM zhanx: No basement here
09:58 PM Tom_L: it had a small cellar for the water heater etc before
09:58 PM zhanx: But I have a "pond"
09:58 PM Tom_L: the rest was crawl
09:58 PM Tom_L: best thing i ever did to this place outside of the garage
09:59 PM zhanx: I was like where is the water? It's a big hole right now
10:01 PM Tom_L: you find a job you like yet?
10:01 PM zhanx: After the electrical is done pouring a pad for the 1 meter cube 3d printer
10:02 PM zhanx: Not yet doing peice meal contracting for now
10:02 PM zhanx: My VA benefits cover this place
10:02 PM Tom_L: not a good time to be looking really
10:03 PM zhanx: True
10:03 PM zhanx: I have interviewed but turned them down
10:04 PM zhanx: Sadly for most people they can't do that
10:04 PM Tom_L: yup
10:05 PM Tom_L: it will take a while but ones with skilz will get good jobs
10:05 PM zhanx: On a good news I am down to 270 and size 36 jeans again
10:05 PM Tom_L: gained after you left the service ehh?
10:06 PM zhanx: Yes I was up to almost 300 and a 42 waist
10:06 PM Tom_L: keep it up
10:06 PM Tom_L: you'll feel alot better
10:06 PM zhanx: I was this size in the army
10:07 PM Tom_L: you're tall though right?
10:07 PM zhanx: Never gonna be little and yes 6'6"
10:07 PM Tom_L: -2-3" or so...
10:07 PM Tom_L: from your back injury
10:07 PM zhanx: I wish
10:08 PM Tom_L: or did they fix that
10:08 PM zhanx: I need to remove some ceiling fans
10:08 PM zhanx: Half fixed
10:09 PM zhanx: Tom remember rue makes fun of me due to boot of death crushing stuff
10:09 PM Tom_L: that one i don't remember
10:10 PM zhanx: I broke a floor once
10:10 PM zhanx: Now instead of deadlifts I do yoga
10:11 PM zhanx: Think a 4" cement pad is enough to overlay old mixed pours ?
10:12 PM Tom_L: with some wire in it sure
10:12 PM zhanx: I pulled all the rotten wood up and it's mixed dirt and pads
10:13 PM Tom_L: they did my basement in 3 pours, the first floor pour they put posts in to support wall braces then they did the walls and after they knocked out the pipes in the floor, poured another 4" of floor
10:14 PM zhanx: K
10:14 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/house/7.jpg
10:14 PM Tom_L: you can see the pipes there
10:14 PM Tom_L: for wall bracing
10:14 PM zhanx: Yep. I am not doing drains or pipes in the floor either
10:14 PM Tom_L: they just busted them out when they were done and poured over it
10:15 PM Tom_L: (the short pipes)
10:15 PM Tom_L: the long ones are in walls now
10:15 PM zhanx: K
10:16 PM zhanx: Either way if you haven't noticed workshop is priority 1 right now
10:16 PM Tom_L: how much weight will it support?
10:16 PM zhanx: Don't know
10:16 PM zhanx: The pic
10:16 PM Tom_L: it should be fine under normal conditions
10:16 PM zhanx: Pipe*
10:16 PM aandrew: man what's with you guys and your 640x480 pics from the 90s :-)
10:16 PM zhanx: Oh the floor work area
10:17 PM Tom_L: aandrew, those were film
10:17 PM Tom_L: i copied them
10:17 PM aandrew: that looks like a fairly big area
10:17 PM zhanx: Aandrew is just jealous
10:17 PM aandrew: I am
10:18 PM zhanx: My workshop will be 50x25
10:18 PM zhanx: Nothing on rue but still
10:18 PM Tom_L: that's a good size
10:18 PM Tom_L: you could put 2 cars end to end if needed
10:19 PM zhanx: Yep
10:19 PM Tom_L: my garage is just 24 sq plus the add on on the back
10:19 PM zhanx: My car port holds 3 cars easy
10:20 PM Tom_L: the add on was instead of a utility shed which would have gotten broken into
10:20 PM zhanx: Weirdly there are hose reels every where
10:20 PM Tom_L: i've parked cars under my patio in storms but it's tight
10:21 PM zhanx: I think I could fit 5 under it easy
10:21 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/patio/patio21.jpg
10:21 PM Tom_L: there's the house after the addition to the back
10:21 PM Tom_L: patio is off the garage
10:22 PM zhanx: I need to take a bunch of photos still
10:22 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/patio/patio20.jpg
10:22 PM zhanx: But it's still kind of a mess
10:23 PM zhanx: Yours is attached mine is across the driveway
10:23 PM zhanx: Oh and I found out today
10:23 PM Tom_L: the garage is detatched
10:24 PM zhanx: This place used to have natural gas wells
10:24 PM Tom_L: huh
10:24 PM zhanx: Was not told that
10:24 PM Tom_L: good or bad?
10:24 PM zhanx: Don't know
10:25 PM Tom_L: do they cap them below grade or above?
10:25 PM zhanx: Concrete pads over them
10:25 PM zhanx: 4x4'
10:25 PM Tom_L: the pipe may be partway full too
10:26 PM zhanx: No clue
10:26 PM Tom_L: careful where you weld until you know :)
10:27 PM zhanx: When i looked at it the grass was high. Now it's hot and irs dying I am like wtf
10:27 PM Tom_L: i'd think if it was leaking it would kill the vegitation
10:27 PM zhanx: True
10:28 PM zhanx: There is a local company that maintenance them. Waiting on the records
10:28 PM Tom_L: they're supposed to disclose that on a sale
10:29 PM Tom_L: the realtor could be liable otherwise
10:29 PM zhanx: They said wells and pond. I didn't realize what the wells meant
10:29 PM zhanx: I thought water
10:30 PM Tom_L: and they weren't specific on purpose
10:30 PM zhanx: You can bet on that
10:31 PM Tom_L: and i'd bet somebody else kept the rights to them
10:32 PM zhanx: But according to my new older thst Jesus neighbor he had one hella garden here
10:32 PM Tom_L: those are good neighbors to have
10:32 PM Tom_L: usually
10:33 PM zhanx: Either side of me are in their 70's and chill
10:33 PM Tom_L: they know the history
10:33 PM zhanx: Yep
10:33 PM zhanx: North and south of me are cattle fields
10:34 PM zhanx: It's 500 yards to next house around me
10:39 PM Tom_L: somewhat rural
10:46 PM rue_bed: heh, we use 14 on 15A circuits here
10:47 PM Tom_L: i think that's about the same here
10:47 PM Tom_L: 20A on 12
10:49 PM Tom_L: https://i.pinimg.com/564x/41/db/e9/41dbe99d8d85cfd0a9255d64244c7190--handy-man-gag.jpg
10:50 PM rue_bed: aandrew, its donated space, I'm keeping the footprint down
10:50 PM rue_bed: doesn't need more detail anyhow
10:50 PM rue_bed: my shop is only 480 square feet, 20x24
10:53 PM Tom_L: and you thought that was big enough when you were building it..
10:53 PM rue_bed: zhanx, most cool overall
10:53 PM rue_bed: well, no, I was only allowed to go to 500
10:53 PM rue_bed: and I thought it was the size of the previous shop
10:53 PM zhanx: K
10:54 PM rue_bed: stuff expanded when moved, so I got bit
10:54 PM rue_bed: I don't know if I need to work till I'm 180 to fund a new house
10:55 PM rue_bed: I think I need a clever trick
10:55 PM Tom_L: start a go fund me?
10:55 PM rue_bed: I'm too honest for most of them
10:55 PM rue_bed: I was pondering that as a *just because*
10:55 PM rue_bed: they do take a huge % of it
10:56 PM rue_bed: its more funding go fundme than youself
10:56 PM rue_bed: but they sleep it in short intervals too
10:57 PM rue_bed: there is growing pot, but its almost worthless here now
10:57 PM Tom_L: crack is where the money is now
10:58 PM Tom_L: it's so widespread here i don't think they care much anymore
10:58 PM Tom_L: they may say they do but it doesn't show
10:59 PM rue_mohr: yea, not going there for sure
10:59 PM rue_mohr: I'm sure there is a lot of money in sex robots, ahahah
11:00 PM Tom_L: few years ago, a trailer house blew up down the street
11:00 PM Tom_L: they were cooking meth and the tanks blew
11:00 PM Tom_L: shot up probably 100' above the trees
11:01 PM Tom_L: the taller tanks, not the bbq ones
11:04 PM Tom_L: i'll just stay poor and keep whittling stuff out on the mill til i retire
11:05 PM rue_mohr: yep
11:07 PM Tom_L: kid went back to work after a 14 day quarantine
11:07 PM Tom_L: test results are still out but no symptoms
11:08 PM Tom_L: somebody at his work tested +
11:08 PM Tom_L: so they all had to get a test and wait
11:18 PM rue_mohr: so, our prim. is really making news with the thing he pulled
11:18 PM aandrew: hm?
11:19 PM rue_mohr: paying a group that fed a bunch of money back to his family?
11:19 PM aandrew: oh yeah
11:19 PM rue_mohr: contracted for something or other
11:19 PM aandrew: fucking hell
11:19 PM rue_mohr: not often he does something big enough for me to hear about
11:19 PM rue_mohr: why are all our leaders such nitts
11:20 PM aandrew: the only thing these nouveau liberals have kept from the old party was teh scandals
11:20 PM Tom_L: nobody votes intelligently anymore
11:20 PM rue_mohr: all the choices are fails
11:20 PM rue_mohr: look at your last lineup
11:20 PM Tom_L: wanna get stabbed or shot.. you pick
11:20 PM aandrew: there is an incredible lack of leadership
11:21 PM aandrew: none of these fucking parties have any leaders you can vote *for*
11:21 PM rue_mohr: someone involved in so many scandals nobody wanted to go near her, or Trump
11:24 PM rue_mohr: zippo:/morfiles/programming/c/avr/Atmega8/resistorbox$ units 1weekend minutes
11:24 PM rue_mohr: Unknown unit 'weekend'
11:24 PM rue_mohr: well damnit
11:24 PM rue_mohr: 2880
11:25 PM rue_mohr: there, the tea is on for the weekend
11:25 PM rue_mohr: should I do the RGB 7 segment?
11:25 PM rue_mohr: quite a lump of wires
11:26 PM aandrew: I'm curious about this ancient cpu to do a timer thing
11:26 PM rue_mohr: ancient?
11:26 PM rue_mohr: my 386 counter? something you have going?
11:26 PM aandrew: 286 for an address bus or something?
11:26 PM Tom_L: unless it's tube it's not 'ancient'
11:26 PM aandrew: no it's something you're doing
11:26 PM rue_mohr: ah, the 17 bit counter
11:26 PM rue_mohr: for the sine wave rom
11:27 PM aandrew: yeah what are you doing?
11:27 PM rue_mohr: I think it has to be a 386
11:27 PM rue_mohr: so, I have an image of a sine wave, in pwm
11:27 PM aandrew: why a cpu? whawt's wrong with a 555 and a counter?
11:27 PM rue_mohr: bit 0 is the "above 0" pwm, and biut 1 is the "below zero" pwm
11:27 PM aandrew: yes usually you store a quarter sine
11:28 PM rue_mohr: its on a 1M rom, so to 'play' it I need a 17 bit synchronous cuonter
11:28 PM aandrew: and if you haven't heard about them, checkout don lancaster's magic sinewaves
11:28 PM rue_mohr: hmm, I wonder if I could bend the counter
11:28 PM rue_mohr: but the problem is the 17 bit counter
11:29 PM rue_mohr: it would be 5x 74ls161
11:29 PM rue_mohr: which is awefull
11:29 PM Tom_L: 1 fpga
11:29 PM rue_mohr: or 3 74ls393 + a synchronizer
11:29 PM rue_mohr: yea
11:29 PM aandrew: small fpga
11:29 PM rue_mohr: kinda I'd need to put a pretty big table in it
11:29 PM aandrew: you don't need a synchronizer if you pulse the OE of the eprom
11:29 PM aandrew: rue_mohr: no just for the counter
11:30 PM Tom_L: 74LV8154 +1
11:30 PM rue_mohr: the idea is that the bit0/1 of the rom IS the pwm
11:30 PM rue_mohr: wait, whats the 8154
11:30 PM Tom_L: dual 16 bit
11:31 PM rue_mohr: counter?
11:31 PM rue_mohr: wtf
11:31 PM Tom_L: what it says
11:31 PM rue_mohr: why didn't this come up earler!?
11:31 PM Tom_L: nobody asked
11:32 PM rue_mohr: ouch tho, they pushed it thru an 8 bit io
11:33 PM rue_mohr: aandrew, the output of the rom isn't latched tho, and a latch is one of the sync options
11:34 PM rue_mohr: ok, I'm catching up....
11:34 PM Tom_L: and i'm fading off
11:34 PM Tom_L: gnite
11:34 PM aandrew: yeah I should be sleeping
11:34 PM rue_mohr: gnight, thanks
11:34 PM rue_mohr: the 1/4 works better with a cos wave
11:35 PM rue_mohr: actaully that makes the whole thing a bit complex
11:36 PM rue_mohr: as the count needs to reverse
11:36 PM rue_mohr: not necissarily for an fpga, but for a lookup
11:38 PM aandrew: an up/down counter doesn't sound that bad
11:38 PM rue_mohr: I'd like to avoid an fpga
11:38 PM aandrew: and you were looking at full blown CPUs before
11:38 PM rue_mohr: but the cpu as just a counter
11:39 PM rue_mohr: there might be a state machine solution with the 1/4 table
11:43 PM rue_mohr: no
11:43 PM rue_mohr: non-fpga wise
11:44 PM rue_mohr: it looks like a 386 as a 17 bit counter is the easiest hardware approach
11:44 PM rue_mohr: and a full on ROM