analog&RFmodels
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i have had good luck in the past using "surf boards" that i get from digikey. i usually trim them to remove UN-needed space. use very small tip 20 watt iron, pre-tin the board and the part legs, and tack just one pin...

very good idea - could even be extended to two break lines - like maybe dacs closest to cpu and 5v tolerance parts out on the end so that if you wanted dacs but didn't need 5v tolerance you use the break line furthest...

or even a diode so that the voltage is <6 new cells and drop is semi constant with current either junction for 0.5-0.6 or barrier for 0.3-0.5 volt drop

did some tests three years ago - temp are ir spot meter looking at top center of cpu while air around board is slowly heated at 240 mhz current was 92 ma and ok until top of chip 90 deg c at 256 mhz current was 99...

i don't think he is speaking of the 1170, but rather a bigger T4 with 1062 mpu nice to know 1170 has an internal dac

if there is room i would vote for single or dual dac similar in performance to tlc/t3.5/t3.6

when you say this just after my post it makes me feel guilty!

one or more dac rather than none comes in handy for creating pseudo sin waves for modulating a radio. will work over a wide frequency range and compared to square waves requires far less external filtering to keep...

your Snooze library is fantastic! it will certainly be welcome when it happens for Teensy4. i have been compiling and running on Teensy4 for 3 weeks now and have become at least a little familiar with it. have been...

your voltages look very much like what worked here - my final ver tested like this: 720 75 mv lower than std, 2% reduction in current, about 2.0:1 longer life 816 100 mv lower than std, 5% reduction in...

am i putting this in the right place? just some food for thought... in attempting to fit the data in NXP app note AN12170, to an equation, it seems that when warm, T4 mcu life is on average in inverse proportion to...

i'm sure you know this already, but V0 will not compile some adc code if target is Teensy LC (and i suspect same for Teensy 3.6) altho just fine w Teensy4 (see my earlier post this thread re how well V0 and T4 adc...

thank you for looking on and off - as i said in a previous post - almost of the library code is way above my pay grade. the work arounds we have found are good enuf for relatively slow work like fsk over a voice...

there is a place early in the code where it watches for a change on the pin - loop label is wtchg or something like that - did not do a timeout on elapsed millis because the radio messages are often as much as 60 sec...

in thread "Teensy 4 FreqCount compile error" one of the posts has a github link you only have to do minor editing to 2 files in the lib and then T4 under 1.48 will compile FreqCount functions

i got in too big a hurry doing editing of post #25 this thread - did some "harmless" editing that i posted and did not compile it (sloppy sloppy) of the two pgms in post 25 the first pgm (does not do overhead timing)...

i agree, however, i have glanced thru the library files and can only say - way above my pay grade. i think you or some other professional programmer will have to tackle that.

these are the codes i am testing with lately after you tie the two input pins together per the comments near top of code, apply sq wave 0-3.3 or 0.1-2.8 v fin there t4 10k series each pin then tie together to gen...

here is an update to post #20 this thread: caught TLC w first two FreqMeas measurements that did not match once in a blue moon so: TLC 48 mhz smallest 40 microsec delay after last ..begin AND 3 dummy reads...

i am confused by post 2 and 3 - the whole reason i created "FreqCount caution" was to call attention to the FreqCount funny whereas post 2 and 3 focus on FreqMmeas which maybe belong under "teensy4 FreqMeas problem?" ...

after running several hundred cold starts the 100% safe thing to do is on FreqMeas, delay for 40 microsec just after ...begin AND do two dummy cycles before real measurements, this only costs about 52 microseconds ...

it took me so long to get back to the bench that you had already run and improved the code you had posted in post #13. but my results with it were first one or two samples in error then all ok and like you i got avg of...

here is a piece of t4 code that shows the fmeas problem i am seeing, and seems to at least isolate the nature of the problem. and turns out tlc does it too - in my old application it was "invisible" but with this...

the number returned has terrible wander - ie not repeatable - as if the timer is not getting reset each time or is not synchronized that output is listed in the orig report a couple of posts later is the same code...

manitou, thank you for the feedback defragster, thank you for the feedback i ran the code you were nice enuf to post w 22 and 23 tied together - ran fine very near 800.0 every time

ok pin 22 is still correct - makes sense, when i turn the generator off dead standstill for awhile i tried 500 hz 1000 hz and 1500 hz - all wander terribly as if the internal timer is not getting reset before...

it just dawned on me that not everyones arduino will use main (tls and t3.6 do it and one of the senior members showed me what to edit so t4 will do it too) so i can pull up old pgms and compile t4 to double check all...

what is IDE format ? that was select all then copy in arduino ide, paste to notepad, flash drive, web computer, paste into the post - that was what i ran to get the output you see. or are you speaking of the fact that...

i have used Bumblers' V0 adc library (search in technical for "adc") to get 12 bit conversions in about 0.8 us going 10 or 8 bits speeds it up some but not a lot. since that is your low end i think you need an...

i have a pgm running that uses good sine generator and float fft to "test" the T4 adc doing 8 time domain data sets averaged with adc hardware averaging of 8, and HIGH_SPEED for t convert and t sample (using Bumblers'...

Bumbler, V0 works well. took some code that does interval timer driven 12 bit manual conversions (value=adc->analogRead(readPin) every 4 microseconds (250 khz). In the T3.6 at 180 mhz atod hardware averaging was 1,...

Kurt, got away from it a few hours and found my oversight - works just fine this end win7 pro x64, arduino 1.8.5, teensyduino 1.48 release, setup w loop or just main both work with teensy4. thanks again for your...

Kurt, no joy trying to duplicate, copied main.cpp from teensy3 dir to teensy4 dir edited starup.c near top startup.c #include "imxrt.h"

thanks for taking the time for that - i will try to duplicate this end

you will be impressed yes - at a glance the 133 looks big but the clk/iq stays fairly constant - the proportionality only grows 10 percent over that range 89/600 = 0.148 110/720 = 0.153 133/816 = 0.163 i...

Kurt, i am a dummy - after seeing your post i realize that the error messages should have led me where i needed to go, but since i had not ever been using setup() and loop() for the last two years and had forgotten...

i think i see your point - i will dump using main() - it is not that much trouble to go back to main() when testing under GNU C on the PC thanks for the feedback

Kurt, please see my previous post - most Teensy will do main() but not t4.0 yet - needs setup() and loop() that's ok - the massive speed increase is worth having to make changes when using GNU C on the PC for...

you were right - t4 cannot use main() - must use setup() and loop() fyi- teensy lc,3.5,and 3.6 are all ok with main() - so i just thought that it was a given thank you having such insight - the error message would...

i had no idea that could be teensyduino. i will re-do one of the two cases with setup() and loop() and report results. thank you for the feedback

another case of arduino 1.8.5 and teensyduinod 1.48 released never compiles- at least nothing i have tried will compile. running win7 pro x64 first case i posted was earlier today - maybe 4 posts back in all cases...

hi Kurt, i just got tired of having to make slight code changes between Arduino and GNU C compiler on the PC (i test what i can on the PC) so i tried to see if Arduino would take a standard format and i could keep...

hi all, is this the right place to put this ? this code compiles/runs fine teensy3.6 180 mhz debug (debug only) but crashes during compile for teensy4.0 600 mhz debug am running win7pro 64 bit, Arduino 1.8.5,...