#avr Logs

Sep 05 2022

06:31 AM rue_mohr: anyone here work with the avrdude project?
06:40 AM rue_mohr: or know how to write avrdude.conf files :)
08:10 AM LeoNerd: Anyone had much success with the new ATtiny chips and the internal temperature sensor? I seem to have partial success.. In that, I have some numbers, and the numbers get bigger when I hold my finger on the chip to heat it up, and then they gradually get smaller again
08:11 AM LeoNerd: But attempting to convert the number into actual degrees C leads to the number 35. Which isn't entirely implausible but that's a bit hotter than it is today. I'd say more like 18, 20ish at most
08:11 AM LeoNerd: The number seems close enough to suggest I'm doing it about right, but it's not -quite- spot on
08:31 AM Phantom: the ADC may have some offset and the chip itself heat up
09:08 AM cehteh: LeoNerd: that internal temperature sensor is pretty low res iirc and not calibrated
09:09 AM cehteh: iirc atmel had some appnote for that
09:10 AM LeoNerd: Low-res, sure. That would mean it would jump in steps
09:10 AM LeoNerd: Calibration comes from the SIGROW
09:15 AM cehteh: SIGROW?
09:16 AM LeoNerd: Yes
09:17 AM cehteh: ah new attinys have calibration
09:18 AM LeoNerd: The really-newer ones have two-point calibration, at 3.3V and 5V
09:18 AM cehteh: yeah didnt know
09:19 AM LeoNerd: It's possible what I have here is just the 3.3V calibration values, which aren't so useful since I'm running at 5V
09:30 AM cehteh: yeah temperature calibration is fun
09:30 AM cehteh: can you temporarly switch to 3.3v? store the temp, switch to 5v calibrate with the stored temperature?
09:30 AM LeoNerd: Hmmm perhaps so...
09:30 AM cehteh: or just calibrate with some other temperature probe
09:31 AM cehteh: well dunno what your application is but i prolly aim for calibrate the ulrasonic sensor with some known distance at first, if possile
09:32 AM LeoNerd: Yeah I can do that easily enough, but it does vary with temperature.. being my point
09:32 AM cehteh: having float switches for upper and lower levels?
09:32 AM cehteh: mkay
09:32 AM LeoNerd: I want a gauge reading
09:32 AM LeoNerd: Imean it's fine without the temperature calibration, it just means the value varies a little over the day because of temperature
09:32 AM cehteh: or pressure sensor at the bottom of the barrel instead sound
09:33 AM LeoNerd: It's not hugely problematic
09:33 AM cehteh: well there are so much options
09:34 AM cehteh: pressure sensors are very precise nowadays even in air you can measure the pressure difference between some tens of cm in heigt
09:34 AM cehteh: for water thats even better
09:35 AM LeoNerd: This ultrasonic sensor can easily give me a mm
09:35 AM LeoNerd: I'm surprised how good it is
09:35 AM cehteh: yes
09:36 AM cehteh: as long the surface is pretty calm and theres no corrosion on the sensor, mold, biofilm, humidty problems
09:38 AM LeoNerd: Ahah, here we go. TMP36 - a 5V powered analog-output temperature sensor. Since I have to run 5V up to the thing anyway, that's just one more wire to give me temperature
09:38 AM LeoNerd: It'll be good enough to mostly null out the variation
11:10 AM cehteh: ±2°C accuracy over temperature well good enough
11:11 AM cehteh: how much fill difference would that make?
11:11 AM cehteh: prolly not much
11:12 AM cehteh: esp much better than the internal temp sensor since you only need to expose the sensors to the environment and seal the rest of the electronics away
11:12 AM LeoNerd: Yah
03:39 PM WormFood: my old cordless phones ran on 900 Mhz, or 2.4 Ghz. Of course, the RF section is a module, but I can't find any information printed on it. Has anyone found any hacking information for these type of modules? I don't even know what to search for.
04:38 PM Phantom: afaik they are semi-custom made
04:48 PM Rab: I have seen old mobile phones and radios with digitally-controlled RF sections in shielded cans. They look like they could be modular, but they're built onto the main PCB. Usually the frequency is set by a programmable PLL, like e.g. MC145170.
04:48 PM Rab: https://www.nxp.com/docs/en/data-sheet/MC145170-2.pdf
04:50 PM Rab: You can easily program these with a microcontroller, but it's not like the RF section is a "smart" module you can send e.g. AT commands to.
04:50 PM WormFood: the ones I have here are modules
04:50 PM Rab: That might be older and less integrated than what you're thinking of.
04:50 PM WormFood: I'm very familiar with PLLs. I used to fix 2-way radios professionally
04:51 PM Rab: Got it. Do you have any pics of the modules?
04:51 PM WormFood: I can get some pics
08:04 PM rue_mohr: no how about avrs?
11:06 PM nonlinear is now known as zeroxray