Serial Voltmeter using the
PIC16C71 - Building a serial voltage meter to measure
from 0 to 5 volts DC is actually pretty easy. Using MeLabs PicBasic, and Microsoft's Visual Basic Version 5
Pro. You need Visual Basic Pro version because you will have to use Basic's MSComm control. This control is
not available in the Visual Basic 5 "Learning" Edition. The PIC16C71 simplifies the task even more by having
a built in A/D converter. Pins 17, 18, 1, 2 are the analog inputs AIN0, AIN1, AIN2, AIN3 respectively. . .
Standalone Digital Voltmeter Uses A Multichannel ADC - 11/15/12 EDN Design Idea Monitor several different voltages with one instrument. This
Design Idea was realized for voltage/current measurement on a four-channel analog voltage source but has wide
use in many other applications. The design is based on the Atmel ATmega8-16AC microcontroller and the MAX1230
12-bit ADC (references 1 and 2). Although the microcontroller has an internal 10-bit ADC, it’s more efficient
to use an external multichannel ADC than to multiplex more analog channels to the ATmega8-16AC differential
ADC inputs. . . [by Branislav Korenko]
Talking Voltmeter - Ever needed to measure a voltage without taking your eye off something? If so, then this is
the project for you! The Orton Talking Voltmeter takes a voltage measurement in the range 0-5 Volts and then
reads it out to you to two decimal places (i. e. to 10mV resolution). The design illustrates the use of the
10 bit ADC in the PIC, as well as pulse width modulation (PWM) for analogue output. This project also
illustrates how to squeeze every last word of program memory out of a PIC! Sound samples consume almost all
of the on-chip flash memory, and even that was after some pretty brutal trimming of the samples and a drop in
resolution to seven bits. Even after all that, the samples are about as brief as you can get without becoming
unrecognisable. . . [Karen's Microprocessor Projects]
The HOTCHECK: Extended Scale
Voltmeter and Battery Tester - A small and east to
build device based on the LM3914 voltage measurement integrated circuit can be used to measure the output
voltage of rechqrgeable battery packs. A built in discharg cir4cuit places a 300mA load on the battery that
can be activated by the press of a button. . . . [C. Brent Dane AMA 345702]
Understanding and selecting RMS voltmeters - 05/11/00 EDN Technical Article: Failing to verify ac-voltmeter accuracy before conducting
rms-noise measurements may cause highly misleading results. . . . [by Jim Williams and Todd Owen, Jim
Williams, EDN's most revered contributor-At 63 years of age, Williams passed away in June 2011 after a
stroke.]
Volt Meter with Video Output - Video-DVM is a very cheap DVM that shows how an output as complex as a videocomposite
signal can be generated entirely in software: two I/O pins and three resistors are all the hardware required.
Connected to any TV set it displays voltages, included max and min peaks, using both giant digits and an
analog bar-display. A serial data output for computer data logging is provided, too. . . . [Alberto Ricci
Bitto]
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