Arduino UNO digital output voltage (5V) - how it gets the 5V from USB power?

-

hi folks. when arduino (eg uno) gets power usb cable only, how digital output pins 5v?

the outputs @ 5.0 v (from multimeter measurements) when output pins high. if usb voltage 5v, thinking there voltage drops internal arduino result in less 5v output. in advance.

quote
if usb voltage 5v, thinking there voltage drops internal arduino result in less 5v output.
why think that? not case.

there no voltage drop if there no current flow. put 220r resistor high input ground , measure voltage again see voltage drop 5v.


Arduino Forum > Using Arduino > General Electronics > Arduino UNO digital output voltage (5V) - how it gets the 5V from USB power?


arduino

Comments

Post a Comment

Popular posts from this blog

Error: ‘for’ loop initial declarations are only allowed in C99 or C11 mode - Raspberry Pi Forums

-
hey everyone, i'm trying compile simple code on rpi3 using geany. code written using code::blocks on windows , working without problem. errors i'm getting are: untitled.c:33:5: error: ‘for’ loop initial declarations allowed in c99 or c11 mode , untitled.c:33:5: note: use option -std=c99, -std=gnu99, -std=c11 or -std=gnu11 compile code understand code not problem way i'm compiling it. can give me advice? you need add 1 of suggested options compile command configured in geany, in menu.. build -> set build commands add "-std=c99" after "gcc" in compile , build boxes. (i'm looking on mint pc expect version on pi same). petero raspberrypi
Read more

class MPU6050 has no member named begin

-
hi all, as working out scripts wich me make winddirection meter gy-87 calibrate compass sensor on board. i using script "hmc5883l_calibrate_mpu6050" korneliusz jarzebski. i fault "class mpu6050 has no member named begin" /*   calibrate hmc5883l + mpu6050 (gy-86 / gy-87). output hmc5883l_calibrate_processing.pde   read more: http://www.jarzebski.pl/arduino/czujniki-i-sensory/3-osiowy-magnetometr-hmc5883l.html   git: https://github.com/jarzebski/arduino-hmc5883l   web: http://www.jarzebski.pl   (c) 2014 korneliusz jarzebski */ #include <wire.h> #include <hmc5883l.h> #include <mpu6050.h> hmc5883l compass; mpu6050 mpu; int minx = 0; int maxx = 0; int miny = 0; int maxy = 0; int offx = 0; int offy = 0; void setup() {   serial.begin(9600);   // initialize mpu6050   while(!mpu.begin(mpu6050_scale_2000dps, mpu6050_range_2g))   {     delay(500);   } how slove error? any apreciated. kind regards, ilioss what compiler complainin
Read more

missing filename after '-o'

-
i'm new writing in arduino , trying program "ultimate robot kit blue". in uploading first motor test, error message keeps coming says: avr-g++: error: missing filename after '-o' exit status 1 error compiling. invalid library found in /users/dennisleary/documents/arduino/libraries/makeblock-libraries-master: /users/dennisleary/documents/arduino/libraries/makeblock-libraries-master invalid library found in /users/dennisleary/documents/arduino/libraries/makeblock-libraries-master: /users/dennisleary/documents/arduino/libraries/makeblock-libraries-master i've been trying robot , running quite time , appreciated! you have not installed library correctly or correct name.  however, did not post code , did not post complete message guessing.  not @ guessing.  please try again, following instructions follow. to post code and/or error messages: 1) use ctrl-t in arduino ide autoformat code. 2) paste autoformatted code between code tags (th
Read more