#avr Logs

Aug 09 2017

01:49 AM JanC_ is now known as JanC
08:39 AM kenny___ is now known as kenny
10:23 AM Mali_ is now known as Mali
04:10 PM renn0xtk9: If I look at oscilloscope the output of a pin, if the pin is flying(not connected to circuit nor to a pulldown resisotr) I should be able to see the tension that the muc applies on it no? it stays 0v :S
04:11 PM xentrac: yes
04:11 PM antto: renn0xtk9 your scope probe (in dc-coupled mode) is like a very big resistor to ground
04:12 PM xentrac: in fact even if it is connected to a circuit or resistor unless that circuit is capable of sinking or sourcing quite a lot of current, hundreds of milliamps
04:12 PM xentrac: yeah, make sure you're not ac-coupled
04:12 PM antto: if the pin is floating, you might still see "0V" due to your probe acting as a very weak pull-down resistor, but you'll also potentially see noise
04:13 PM enh: and you probably mean floating, instead of flying
04:13 PM xentrac: if you're ac-coupled then any steady voltage will look like 0
04:13 PM antto: they float, enh.. they aaall float
04:13 PM antto: ;P~
04:14 PM xentrac: what are they made of? I thought all three of copper, aluminum, and tin would sink in water :)
04:14 PM enh: whatever it is, it probably won't fly by itself
04:15 PM enh: maybe if attached to a baloon...
04:15 PM antto: aerated aluminum, of course
04:15 PM enh: ethereal metal
04:16 PM renn0xtk9: okay well it seems I got no signal comming out of the pin, looking at my source code now :S
04:16 PM enh: Remember to set the pin to output before setting it to high
04:23 PM renn0xtk9: how can I ask for the value of somehing that is defined with #define at compile time ?
04:31 PM polprog: #error?
04:31 PM polprog: maybe
04:32 PM polprog: there was a directive that printed sme info
05:01 PM renn0xtk9: I do this stuff https://www.google.de/search?q=IR+diode+with+transistor&tbm=isch&imgil=ypsYo9gGshq5JM%253A%253BP_vIpM5v8B7ILM%253Bhttps%25253A%25252F%25252Farduino.stackexchange.com%25252Fquestions%25252F36758%25252Fusing-a-transistor-to-get-100ma-on-a-ir-led&source=iu&pf=m&fir=ypsYo9gGshq5JM%253A%252CP_vIpM5v8B7ILM%252C_&usg=__JOsG24tyXOFtTJV9a-xYm0JUlLk%3D&biw=1920&bih=922&ved=0ahUKEwjT2sPQisvVAhXI0RoKHdQqCV0QyjcIQA&
05:01 PM renn0xtk9: ei=3XyLWZP4Nsija9TVpOgF#imgrc=ypsYo9gGshq5JM:
05:01 PM HighInBC: hehe
05:01 PM HighInBC: nice try
05:03 PM renn0xtk9: HighInBc^^ See link in https://pastebin.com/vDpnehPJ
05:04 PM HighInBC: sooo https://cdn-learn.adafruit.com/assets/assets/000/023/275/medium800/light_ir_output.png
05:04 PM renn0xtk9: yes
05:04 PM HighInBC: nice, 2222s are handy
05:04 PM renn0xtk9: but instead of connecting the muc pin to the base I ground it, just to make a try
05:05 PM renn0xtk9: transistor is BC557
05:05 PM renn0xtk9: I got a 1.2 Volt accross the LED
05:05 PM renn0xtk9: I would have expect 0 since base current=0 -> collector current =0 -> no current in LED and no tension ?
05:06 PM renn0xtk9: I would have expected the 5v to be accross collector and emittor of transistor
05:06 PM renn0xtk9: (I try this coz I got the feeling that the LED is inverted (like it is on for zeros and off for ones :S )
05:10 PM renn0xtk9: (I also got a 100 ohm resistor before the LED)
05:14 PM HighInBC: some types of transistors are opposite, they are off when charged and on when grounded
05:14 PM HighInBC: not sure about yours
05:15 PM renn0xtk9: I checke the datasheet, it is a pnp so should be same as on schematcis
05:16 PM renn0xtk9: correction npn, but yes like on schematic ^^
05:17 PM HighInBC: datasheet for the bc557 says PNP
05:17 PM HighInBC: http://www.onsemi.com/pub/Collateral/BC556B-D.PDF
05:17 PM HighInBC: the 2n2222 is a npn
05:43 PM Lambda_Aurigae: PNP=Points In People...NPN=Not Points In
08:07 PM NoHitWonder__: what was that small and cheap stm32 board?
08:07 PM Lambda_Aurigae: bluepill
10:11 PM enh: hi
11:28 PM enh: silent here today
11:46 PM day_ is now known as daey