#robotics Logs

Jun 01 2017

12:00 AM mrdata: 50Hz is 20 ms
12:02 AM mrdata: did yesterday's effort get burned? or kept?
12:02 AM rue_house: its all good
12:02 AM mrdata: ok, good
12:02 AM rue_house: I have a trail
12:02 AM rue_house: something odd tho, it seems that the bus is runing at 18Mhz, when I expected 36Mhz
12:03 AM rue_house: and it gets stranger
12:03 AM rue_house: OK no
12:03 AM rue_house: I'm just an idiot
12:03 AM theBear: welcome to my world <wink>
12:03 AM rue_house: I was toggling it at 1khz, which is 0.5Khz
12:03 AM rue_house: so it IS 36Mhz
12:03 AM mrdata: good
12:05 AM theBear: actually you measured more than a few things over the years mr rue_house .... you ever had a selection of different age and likely supplier/manuf new and used tact switches that while they in teh low-double-digit range of ohms when on, none of them are low enough to make an average meter beep on beepey setting ?
12:05 AM mrdata: i ran into a real clock problem with an ATmega328 board, perhaps because it was using an external clock crystal. the serial port was running at the wrong speed
12:05 AM rue_house: ok, what is the highest number (and multipler) below 65536 I can divide 36Mhz by to get 50hz
12:05 AM mrdata: but it wasw an off-by factor of 2 i forget which way
12:05 AM rue_house: mrdata, anything over 9600 becomes dodgy unless you have a clock set up for serial
12:05 AM rue_house: and there is that x2 flag
12:06 AM mrdata: 36 MHz / 50 Hz is 720,000
12:06 AM mrdata: you have to prescale at least 12x
12:06 AM rue_house: theBear, I'v had a variety of sensitivites on meters
12:06 AM rue_house: some will beep at about 500ohms, some not till 5
12:06 AM rue_house: I have two dividers
12:07 AM rue_house: in chain
12:07 AM rue_house: I need one of them to be as large as I can
12:07 AM mrdata: rue_house, oh yeah i set the arduino for 9600 but had to talk to it at 19200
12:08 AM rue_house: 12 and 60000
12:08 AM mrdata: yeah
12:08 AM rue_house: so, that means I can measure an incomming current pulse with a resolution of 60000 counts
12:09 AM rue_house: better than a 10 bit adc :)
12:09 AM mrdata: coolio
12:09 AM rue_house: dotn know how to set that up yet even
12:09 AM rue_house: and I dont know how to mux it
12:10 AM rue_house: I dont know if I can get 4 channels of input capture from a timer
12:10 AM rue_house: maybe I can
12:10 AM rue_house: ooh geez, I have to remember these are 3.3V too
12:11 AM rue_house: so maybe input caputre should be my next goal
12:11 AM rue_house: er, I'll finish the 50Hz project
12:15 AM * rue_house goes insane
12:15 AM rue_house: hahaha it compiled first try!
12:16 AM theBear: rue_house, mmm, i never looked up/known the exact cutoff on this meter, but this is the first time i remember it not-beeping when i expected it would, and first time i recall tact switches that didn't look a lot like a bit of wire when the button was pressed
12:32 AM rue_house: iiiinteresting, so the uart uses the gpio system
12:32 AM rue_house: you have to enable the clock sysstem for the uart itself, and the gpio system its using
12:32 AM rue_house: theBear, some of those swtiches can get pretty bad
12:35 AM rue_house: ok I have 6 working stm32 projects
12:35 AM rue_house: so, what next
12:35 AM rue_house: input capture, or adc
12:35 AM theBear: mmm, i was surprised that my (far from recently purchased) new ones didn't measure any lower
12:35 AM rue_house: ? how are the meter leads?
12:38 AM rue_house: picked up a few ohms?
12:38 AM theBear: course i do smoke a lot and they been in the house with me doing it for years.. acceptable, haven't checked them today, but i tend to keep them below .1 or .2 ohm when shorted, habit i got into back when i biased valve output stages at work all the time and often had to hand-match a set of 2 or 4 1r resistors to measure current per tube
12:38 AM rue_house: :) I'm making good headway on the stm32 thing
12:38 AM theBear: they sure as heck ain't picked up 20ohms, and they beep without hesitation when i slip off the little switches and they touch
12:38 AM rue_house: are they metal core or carbonized rubber?
12:38 AM theBear: you sound excited, this your first foray into stm32 land or you just getting things done fast ?
12:38 AM * rue_house chants "smash one!"
12:38 AM * rue_house prods anniepoo
12:38 AM rue_house: "smash one! smash one!"
12:38 AM theBear: metal i assume, you know, standard little teeny square or round 4 and 2 pin mount thruhole clickey tact switches, like the buttons on a modern tv or car stereo front panel
12:38 AM rue_house: "smash one! smash one! smash one!"
12:38 AM rue_house: I'll take a detour and import my avr number printing library
12:38 AM rue_house: then get some code reporting an adc channel
12:43 AM rue_house: "smash one! smash one! smash one!"
01:08 AM rue_house: Jak_o_Shadows, I'm up too late, you awake?
01:12 AM mrdata: from scrollback i reckon he'll wae in 3 hrs ish; but i'm off to bed, nn
01:12 AM mrdata: *wake
01:22 AM rue_house: hmm makefile dosn't slurp up all the .c files
01:56 AM rue_bed: I'll have to see if I can maul in what I have for the avrs
03:01 AM Jak_o_Shadows: rue, you seem like you're going well.
03:01 AM Jak_o_Shadows: You've got a lot more experience calculating timer speeds and stuff like that than I do.
03:03 AM Jak_o_Shadows: Also, yeah, I have not had great luck getting the makefile to auto-compile stuff based on #includes
03:03 AM Jak_o_Shadows: SO i gave up
09:14 AM rue_house: you dont base it on includes :)
09:14 AM rue_house: Jak_o_Shadows, want a hand to get it where I'v got it?
09:46 AM rue_house: ok I think I can see what to do with the makefile to have it work like the avr stuff I use does
12:55 PM anniepoo: sorry rue - didn't get you back on in time, went on, and now I'm off for camping today&tomorrow
05:50 PM rue_house: mmhmmm
06:43 PM nnumerals: rocket launch in 17 mins
06:43 PM nnumerals: http://www.arianespace.com/mission/ariane-flight-va237/
07:28 PM nnumerals is now known as solol
08:50 PM rue_house: yes, we have 15 mins left to modify this makefile or we will have to abort
10:49 PM rue_house: ok, the higer level stuff is getting on its feet, I can print 16 bit numbers to the serial port
10:49 PM rue_house: bit of a fight, with changes to the makefile and all to handle other source files
10:49 PM rue_house: got it!
10:49 PM rue_house: the makefile is tuning up well
10:55 PM rue_house: ok I got that working, so next is ADC
11:00 PM Tom_L: you need a folder for all your stuff
11:01 PM zhanx: he needs a filing cabinet and a storage unit
11:09 PM rue_house: I'm on program 8
11:09 PM anonnumberanon: if rue_house can do it we should all be able to code for ARM!
11:09 PM * rue_house flails
11:10 PM anonnumberanon: flailing your arms, oh i get it now
11:50 PM * rue_house stops his watch
11:52 PM rue_house: ok ... I'm getting values
11:52 PM rue_house: 02059
11:52 PM rue_house: 02050
11:52 PM rue_house: 02043
11:52 PM rue_house: 02250
11:52 PM rue_house: 02164
11:52 PM rue_house: 02119
11:52 PM rue_house: 02087
11:52 PM rue_house: 02067
11:52 PM rue_house: I wonder what pin they are comming from
11:53 PM rue_house: *sigh*