i am currently working with some power supply design and i can say using conventional pots(potentiometer) and rotary switch to adjust the voltage and other stuff is quite old school. so i have decided to go for a bit high tech , actually bit digital.
so here is the solution
Incremental Rotary Encoder
first of all i would like to tell you , these type of rotary encoder is totally digital component so you can't directly replace these with you conventional pots. so lets start what are Incremental Rotary Encoder , Incremental rotary encoders by the looks of it just like a general purpose pot looks like but output is quite different they provide a pair of digital signals that allow a microcontroller to determine the direction of a shaft’s rotation. They can be used to monitor motors and mechanisms, or to provide a control-knob user interface.
for a quick look here is a typical incremental rotary encoder
and hear the output wave form
Decoding with Microcontroller
in this examples we will be decoding the rotary encoder with the help of sate machine.
view of state machine in the wave form
Schematic with PIC18F458
CLIK Here To download Source Code and Firmware.
if you have any problem please leave in the comment section.
hello gaurav
ReplyDeleteplease post the uc code for interfacing rotary encoder
if possible use atmel mega x chips
ReplyDeleteThis code is incomplete, you must do the revision. Program increments the variable just to pin 4 and pin 5, with no requirement to complete full cycles of 10,11,01,00. These can lead to an incorrect reading of the encoder.
ReplyDeletethen how to check all states ?
ReplyDeleteSee before going to use any encoder to interface with the micro find the PPR (Pulse Per Revolution) of the encoder.
ReplyDeleteThe encoder has only 4 states 11,01,00,10 i.e in hex 3,1,0,2 ( Every make has its own state )
So 1st read the state of the encoder, then to detect whether the direction is cw and ccw use the logic.
After the logic Either Increment the counts or, decrement the counts.
Its Simple once you interface its quite easy to handle.
To use XC8 compiler, which part of the code needs to be changed. ?
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