#garfield Logs
Apr 16 2020
#garfield Calendar
02:12 AM rue_mohr: hmmm
02:17 AM rue_mohr: the editor tutorial and my old core work on different paradigms
02:17 AM rue_mohr: need to think about this
02:17 AM rue_mohr: int he tutorial, there is a buffer rendered of the colour attributes for every character
02:17 AM rue_mohr: in my code, I have a linked list of tags for the start and end of attribute blocks
02:17 AM rue_mohr: so I cant really just tell if I'm in the middle of any given block by my character position
02:25 AM polprog: maybe you could store the character position of each tag in the linked list
02:26 AM polprog: grantd, that will have to be updated every time the user types a char but i dont think theres a different approach
02:26 AM polprog: maybe update it after a timeout of not-typing
03:24 AM polprog: "because every EM wave out there travels with a velocity of c"
03:24 AM * polprog eyes the roll of coaxial cable on his other desk
04:02 AM rue_bed: yea, if the user if typing you have to do things
04:02 AM rue_bed: the idea of the tags is to mark the start and end so you dont have to store every position in the file
04:03 AM rue_bed: tho it was more desined for cursors and less for something like syntax hilighting
02:33 PM polprog: https://polprog.net/rozne1/ircjunk/various/nicadchg1.png
02:33 PM polprog: new small project
02:33 PM polprog: nicad charger
02:36 PM polprog: quick and dirty, for 1 sided pcb
03:16 PM rue_mohr: hmmm ok
03:17 PM rue_mohr: where is the voltage limit?
03:43 PM polprog: the supply voltage is the limit.. maybe i should add it with the unused opamp
03:43 PM polprog: thats a good diea
03:43 PM polprog: idea8
03:54 PM polprog: http://www.ti.com/lit/ds/symlink/lm358-n.pdf page 13
03:55 PM polprog: uploaded new schem into ircjunk, refresh
03:56 PM polprog: in that 358 datasheet - that is a push-pull output right? im not sure if the bottom (current control) opamp needs the output resistor
04:01 PM rue_mohr: 358, I'm sure
04:01 PM rue_mohr: I dont know about its common mode operation tho
04:02 PM rue_mohr: those old ones aren't rail to rail
04:02 PM polprog: i will have to change the voltage limit (it's at 4 V now) or make it switchable
04:02 PM rue_mohr: often ya cant be within 1.5V of etiher rail
04:02 PM rue_mohr: thats why I hate the 741
04:02 PM polprog: 358, input voltage range 0 to V+ -1.5
04:02 PM polprog: i will have to change the voltage limit (it's at 4 V now) or make it switchable
04:03 PM polprog: ideally this would allow me to charge both the 7.5 batt pack for the radio and single cells
04:03 PM polprog: so a 4V voltage limit is too high for one cell
04:03 PM polprog: even though the dead cells need at least 2-3 V to take 200mA current
04:04 PM polprog: and the 7.5V batt pack (1250mAh rated) takes 200mA at a voltage of 11.something
04:04 PM polprog: thats where the 12V is from.. so that i could free up the lab PSU while charging the radio
04:05 PM rue_mohr: k
04:05 PM rue_mohr: its something I keep in mind using the older chips
04:06 PM polprog: says diff input voltage range equal to the power supply voltage
04:06 PM polprog: so i think im safe here
04:07 PM polprog: i should put a 400mA polyfuse there on the power input
04:07 PM polprog: ive got some left over
04:09 PM polprog: but is the diode there okay?
04:09 PM polprog: i never did anything like that
04:23 PM polprog: added a jumper to switch the voltage limit between 9.2 and 2.14V
04:26 PM aandrew: yay, custom BLE service and characteristics is working
04:26 PM aandrew: boo, I'm using arduino for it atm
04:27 PM polprog: nice!
04:52 PM rue_mohr: I need to figure out a waterproof linear joystick to put in a cart handle
04:55 PM polprog: just put a rubber cond^Whousing over a regular one
04:55 PM rue_mohr: well
04:56 PM rue_mohr: it needs to take the form of a handle that expands/compresses, and is tied to a potentiometer
04:56 PM rue_mohr: maybe with spring centering
04:56 PM rue_mohr: probbaly with
04:56 PM Tom_L: rubb hose
04:56 PM Tom_L: rubber
04:57 PM rue_mohr: built into a cart handle./
04:57 PM rue_mohr: ?
05:13 PM aandrew: rue_mohr: holy fuck I love that powered wagon
05:14 PM aandrew: rue_mohr: pair of springs holding a piece of linear rail in the middle, the rail has a set of teeth that engage with a sealed pot?
06:16 PM rue_mohr: :)
06:16 PM rue_mohr: huh I didn't think of outright linear rail
06:16 PM rue_mohr: that gives me an idea
06:17 PM polprog: hide your flukes, hide your teks, its time for https://en.wikipedia.org/wiki/Frog_galvanoscope
06:17 PM rue_mohr: haha
06:17 PM polprog: i got a suggestion to move the mosfet to the low side
06:17 PM polprog: i think ill do that
06:18 PM polprog: i will need to redo the coltage limiter but thats okay
06:18 PM polprog: ill be breaboarding it anyway
06:27 PM rue_mohr: hmm interesting
06:28 PM rue_mohr: it looks like non-invasive ventilators are a whole different chapter
06:38 PM aandrew: polprog: lol
06:39 PM polprog: ;)
06:39 PM polprog: nighters
06:56 PM aandrew: ugh
06:56 PM aandrew: fighting motivation issues again
06:57 PM aandrew: neither of these contracts really excite me
06:58 PM aandrew: did anyone else notice how easily everyone just kind of accepted the lockdown?
07:03 PM aandrew: https://i.redd.it/cw4ct4fav7t41.jpg
07:15 PM rue_shop2: I think were all pretty burned out
07:16 PM rue_shop2: haha
07:16 PM rue_shop2: I"m having an issue with the selection of available springs
07:19 PM aandrew: yeah my fastenal account is up near $500 now I think
07:21 PM aandrew: nothing overly specific either... got some ptc connectors and tees, o-rings, some linear bearings, 8mm smooth and threaded rod, 6mm poly tube, some rubber sheet material and some "big" (1.25") 4" long springs
07:21 PM aandrew: also got some n95 filter material and retainers for the half masks
07:21 PM aandrew: that was like 2mo ago though
07:21 PM rue_shop2: hmm sounds steep
07:22 PM aandrew: yeah might have overestimated that
07:22 PM aandrew: let's see
07:22 PM aandrew: 130+115+58+76
07:23 PM aandrew: what's that, $380
07:23 PM aandrew: got a bunch of metric hex socket cap screws from spae-naur too a while ago
07:24 PM aandrew: trying to build up a bit of stock so when I get inspired I'm not waiting
07:24 PM aandrew: that powered wagon though.. brilliant
07:24 PM aandrew: how'd you come across the frame+motors?
07:26 PM ShopMoon: Howcome in kernel space while(*pop++ = 0xFF); DOES NOTHING!!!??!?!?!?!?!
07:27 PM aandrew: ShopMoon: you need ==
07:27 PM ShopMoon: not so :P
07:28 PM aandrew: no, you're trying to fill an area with 0xff?
07:28 PM ShopMoon: atleast I'm pretty sure
07:28 PM rue_shop2: it was a hole cart on its way to the dump
07:28 PM ShopMoon: yes I am
07:28 PM ShopMoon: am i stupid?
07:28 PM aandrew: ShopMoon: why aren't you just using memset?
07:28 PM ShopMoon: == is logic op??
07:29 PM aandrew: well it's kind of dumb, memset will set 4 or 8 bytes at a time and be faster, and I'm not 100% of the logic here
07:29 PM rue_shop2: aandrew, I took the seat and stuff off last year
07:30 PM aandrew: that just doesn't make any sense ShopMoon
07:30 PM ShopMoon: you realy think mem set would be faster?
07:30 PM aandrew: yep
07:31 PM aandrew: the compiler can't even unroll that
07:31 PM aandrew: and I'm still not 100% sure it will fill properly
07:31 PM aandrew: rue_shop2: very nice
07:32 PM ShopMoon: im not consernd with speed (or spelling) but could you elaborate for me why a library call would bu faster cuz I like to learn
07:32 PM rue_shop2: ShopMoon, = is assign it will always be true, == is test
07:32 PM aandrew: ShopMoon: and the termination will be dependant on the contents of the memory pop is pointing to (I think)
07:32 PM ShopMoon: DUH rue but thats the opoint
07:32 PM aandrew: this is just too weird to parse, makes me think you're trying to be slick
07:32 PM aandrew: and I dislike slick programming
07:32 PM ShopMoon: slick?
07:32 PM rue_shop2: he's hacking windows
07:33 PM aandrew: ShopMoon: because memset() will look at the len to fill and fill 1,2,4,or 8 bytes at a time (more if it the function has access to SSE)
07:33 PM rue_shop2: wait *foo++
07:33 PM rue_shop2: *(foo++) ?
07:33 PM rue_shop2: or (*foo)++
07:34 PM aandrew: *foo++ = val is legal, but the result of that is always true
07:34 PM rue_shop2: I dont know who takes prescedence
07:34 PM ShopMoon: reding aandrews statment
07:34 PM ShopMoon: aandrew: define SSE
07:34 PM aandrew: rue_shop2: deref does, think of something like while(*foo++) { do something because the pointer's not pointing to null yet)
07:35 PM aandrew: vector instructions
07:35 PM aandrew: I sped up an FIR filter by allowing the compiler to use NEON (ARM's vector instructions)
07:35 PM aandrew: so it could unroll the loop and operate on 64 bytes at a time, not 4
07:36 PM aandrew: your compiler may even be saying "fuck you I won't code an infinite loop" and just delete that code
07:37 PM rue_shop2: gcc would complain there is no way out
07:37 PM rue_shop2: but that doens't make sense either
07:37 PM rue_shop2: na, ShopMoon I'd say write a longer line of code
07:38 PM rue_shop2: I think I'v worked out this handle controller
07:38 PM aandrew: ShopMoon: what is your exit condition for that loop?
07:38 PM rue_shop2: its not what I was thinking, but its eaiser to do
07:38 PM ShopMoon: well this might get tricky cuz im on WINDOWS :P I probs dont even have memset() or objdump :(
07:38 PM rue_shop2: windws has memset
07:38 PM ShopMoon: aandrew: I dont have one
07:39 PM ShopMoon: I am trying to cause a big fuckup and crash the system
07:39 PM aandrew: ahh
07:39 PM ShopMoon: my next test is to find a wrapper in WIndows C to do an interupt
07:39 PM rue_shop2: he's trying to break windwos
07:41 PM aandrew: that's not much of a challenge. :-)
07:41 PM ShopMoon: unless your trying it seems XD
07:42 PM rue_shop2: hmm , a torsion bar...
07:42 PM ShopMoon: btw aandrew I dont think we'v met in any context before
07:43 PM aandrew: no I don't think so. What do you do (besides try to break windows) ?
07:43 PM ShopMoon: I'm an electrician, and I dable with computers i suppose. you?
07:44 PM aandrew: I design hw/sw for a living and spend a lot of time wasting time looking at interesting things :-)
07:44 PM ShopMoon: cool, do you live in Canada?
07:46 PM aandrew: yes, Cambridge, ON. I was out in BC for a half a year and actually got to visit rue which was cool
07:47 PM ShopMoon: Oh, how did I miss that?? I'm just down the street :P
07:48 PM aandrew: from me, or from rue?
07:49 PM ShopMoon: rue
07:49 PM aandrew: oh shit, didn't know that
07:49 PM aandrew: although it's kind of funny that you've both got multiple nicks for geolocating you
07:49 PM ShopMoon: dicussions are so much better in person for me talking is easyer
07:50 PM ShopMoon: oh, and yes its funny
07:50 PM ShopMoon: I got the idea from him I think
07:50 PM aandrew: I tend ot prefer online because I have either developed a problem with focus or lost the ability to remember
07:50 PM ShopMoon: O
07:50 PM aandrew: but yeah I brought my 10yo son and a bunch of iced tea and rue entertained us for hours
07:51 PM ShopMoon: Maybe I did meet you, did you have the telephony cards?
07:51 PM aandrew: by far the best part of moving to Vancouver, did not like very much else about it
07:51 PM aandrew: yes
07:51 PM ShopMoon: OOOOOHHHHHHHHHh
07:51 PM ShopMoon: Hey man.
07:51 PM aandrew: aha so I did meet you
07:51 PM aandrew: lol
07:51 PM ShopMoon: yeah I took the one with bad ports
07:52 PM ShopMoon: face to a name - cool
07:52 PM aandrew: yes I remember you but have forgotten your name, so you are now forevermore known to me as moon
07:52 PM ShopMoon: Very well
07:52 PM aandrew: (I'm *really* bad with names until I've been around you for a while)
07:53 PM ShopMoon: like most people into technology htiongs
07:53 PM ShopMoon: things*
07:53 PM aandrew: I've also downloaded that movie you recc'd but haven't yet watched it
07:53 PM ShopMoon: I dont recall
07:53 PM aandrew: I don't ge tmuch time to watch tv with the kids if the wife is around. not her doing, just something that doesn't seem to happen
07:54 PM aandrew: the men and their fabulous flying machines I think it's called
07:54 PM ShopMoon: Oh yeah, cuz your kids into planes
07:54 PM aandrew: yep
07:54 PM ShopMoon: right on
07:55 PM ShopMoon: So you dont like "slick" programming eh?
07:55 PM aandrew: general question: is there any real benefit to taking breadboards apart and trying to recondition them (squeeze the fingers of the metal back together)?
07:55 PM aandrew: ShopMoon: no. it tends to bite me in the ass more often than help me out
07:56 PM ShopMoon: no doubt, but I think its my kink ;)
07:56 PM aandrew: I find that if I just write code clearly and comment it well it works better, and the compiler is more times than not better at optimization than I am anyway
07:56 PM aandrew: don't get me wrong, I love to handcode assembly from time to time
07:56 PM aandrew: there's just usually not a really good technical argument why I'd be doing so
07:57 PM ShopMoon: yeah, good clean code is the best, but I like to expand my intimacy with the language when I cam.
07:57 PM ShopMoon: can*
07:57 PM aandrew: for sure, knowing what a language can do leads to better code overall
07:57 PM ShopMoon: :)
07:58 PM ShopMoon: you wana know where I adopted that perticular style for moving memory?
07:58 PM aandrew: I am finding as I get older (I'm 44 next month) that my coding is getting more and more "boring" -- no fancy tricks, but if there is one it's very well documented not only as to what it's doing, but *why* it's being fancy
07:58 PM aandrew: you're not moving memory there, you're filling it
07:58 PM ShopMoon: oh good point but it comes from moving memory
07:59 PM aandrew: yeah memcpy is based on something like that: while (len--) *dst++ = *src++;
07:59 PM aandrew: (that's another op that vector instructions can *really* speed up)
08:00 PM ShopMoon: likely, anyway I got the idea from the implementation of strncpy() in dennis richies book from the 70s
08:00 PM aandrew: oh?
08:00 PM aandrew: nice. I think I have a copy of "the C programming language" somewhere on my bookshelf
08:00 PM ShopMoon: its a COOL book
08:00 PM aandrew: yes
08:01 PM ShopMoon: yeah take a peek its like : while(*dest++ = *source++);
08:01 PM aandrew: http://mixdown.ca/dump/Illustrating_C.pdf is another interesting book for beginners
08:01 PM rue_shop2: ShopMoon, your jacket is here btw
08:01 PM ShopMoon: oh yeah :P
08:02 PM aandrew: a friend of mine said he learned C from it, and I sent my mom that link about a decade ago when she said she wanted to get back into programming
08:02 PM ShopMoon: cool
08:02 PM ShopMoon: ok homies i'm going back to other things now , PEACE
08:02 PM aandrew: also, only tangentially related: check out Usborne's free computer books (largely for kids) -- they made ALL their 80s computer books available for free
08:03 PM aandrew: https://usborne.com/browse-books/features/computer-and-coding-books/ is the main link, and https://drive.google.com/file/d/0Bxv0SsvibDMTZ2tQMmpyOWtsRFk/view?usp=sharing is the book in particular I'm sure I wore out I checked out from the library so many times growing up
08:48 PM rue_shop2: ok, well, the cart might already have a fine mechanism on it
08:48 PM rue_shop2: prettymuch where I was ending up
09:36 PM aandrew: nice. it has a method to detect you pulling/pushing on it?
09:43 PM rue_mohr: no
09:43 PM rue_mohr: I went for an altered attack
09:43 PM rue_mohr: focus on the handle,
09:44 PM rue_mohr: I decided the easiest attack was to put a sprung rotation lever on the end of the handle
09:44 PM rue_mohr: its just about boils down to the control level that was on it
09:44 PM rue_mohr: I still have a problem cause its not at all waterproof
09:45 PM rue_mohr: Id like the design to be able to hold up in rain
09:49 PM zhanx: Evening
09:52 PM rue_mohr: hi
09:52 PM rue_mohr: how are you doing?