# how to build an ohmmeter using msp430

Thank you so much – it is really helpful. The newly created question will be automatically linked to this question. Note that the Yocto-PT100 is not designed to directly return a value in Ohm, but only a temperature. Change ), You are commenting using your Twitter account. Voltage divider formula is given below: voltageoutput = (measured resistance/ (measured resistance  +  R1)) * Vcc. Sorry I’m new to this and still trying to figure it out. Digital ohmmeter is used to measure resistance of any resistance or any circuit. After that measured resistance value can be easily calculated by using below given formula: Measured resistance = R1 × voltageoutput / 5 – voltageoutput; Measured resistance = 10000 × voltageouput / 5 – voltageoutput; Above formula is just rearranged form of voltage division formula. There are two Yoctopuce products which are implemented based on a resistance measure. BTW, first version of my SBW MSP430x2xx flasher (at that time TI LP was not existing) was based on MSP430F2121 and MAX3243 packed inside DB9 connector. Look - unless you build parallel port programmer and use with oldskool computers that have such (Centronics LPT port) or you buy LaunchPad. In this project, we will show how you can build an ohmmeter using an arduino. I could buy one from eBay, but I hope to learn more details of TI flashing related staff, therefore, I will try to do it by myself. 0.0048828 is from ADC -> where you have: ADC(value ) * 5 / 1023, and 5/1023 = 0.0048828, Digital Ohmmeter Good day sir, Can you send me by e-mail the file “.HEX ” Thank you Jimmy, Its 5/1024=0.000488 5v from vref+ and 1024 possible values for de A/d converter (10bit converter 2^10). Canceling the electrical resistance of the probe itself. I would like to see how you can beat the price of LaunchPad :). A variant to this method consists in applying a voltage to the ends of a set of resistors with accurately known values, except for one, and to measure the ratio between the tension at the ends of the unknown resistor Rx with regards to the total voltage. To do so, the ideal is to use a ratiometric converter, that is which accurately measures a voltage ratio. The MSP430 boasts of an internal temperature sensor which is probably new to me who has worked earlier on AVR. By using precision resistors as reference, you can thus obtain very high quality measures: Connecting the Yocto-Bridge for a measure of electrical resistance. I tried a couple of equations on the internet and in the datasheet. For more detail: How to Build an Ohmmeter Using an Arduino, Get Notified Whenever There Is A New Project In Your Desired Category, MAKERLISP MACHINE – AN EXPANDABLE EZ80 CPU CARD RUNNING BARE-METAL LISP, NIGHTMARE ROBOT ONLY MOVES WHEN YOU LOOK AWAY, Use a Momentary or Tactile Switch as a Pushbutton Switch, Make a Web Connected Robot (for about \$500) (using an Arduino and Netbook), © 2013 Powered By Wise Technologies, Use Arduino for Projects | Sitemap | Privacy Policy.