digital voltmeter by usb using ATmega8

faraday

Member

• Jun 16, 2013

• #1

HI all
I wanna to measure an input voltage from -5V to +5V via ATmega8
how can I use USB connection for that?
the output goes to PC via USB connector
and what is the circuit for this project?

 

faraday

Member

• Jun 16, 2013

• #2

I saw it and think it works for USB solution

https://www.obdev.at/products/vusb/index.html

 

K

kubeek

Well-Known Member

Most Helpful Member

• Jun 23, 2013

• #3

the first thing is that to measure +/-5V you need a +/-5V supply, so you will need some chip to make the negative rail. Then you need to feed your measured voltage into opamp to translate it into the 0-5V range that the micro can measure.

 

D

dougy83

Well-Known Member

Most Helpful Member

• Jun 23, 2013

• #4

You don't need a dual supply; a simple resistor divider will work.

You can choose the circuit and base software that suits you best from the demo projects on the page you linked.

 

faraday

Member

• Jun 23, 2013

• #5

Hi
thanks for replying, I did it by resistor divider and VUSB

 

remon7

Active Member

• Dec 13, 2013

• #6

Just try this way. Its only works for low speed usb devices
https://imgur.com/nIVoyqs

 

W

wkrug

Active Member

• Jan 9, 2014

• #7

For that solution I would take a FT232 Chip. That's a USB to serial bridge.
PC drivers are availible at the FTDI Homepage ( VCP Driver ).
At Controller side You can use the Integrated USART. That will make the programming and communication easy.