Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

How does it work 12 steps rotary encoder COM-09117

Status
Not open for further replies.
S

shemo

Advanced Member level 4
Joined
Apr 26, 2002
Messages
105
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,296
Activity points
709
https://www.sparkfun.com/products/9117

1)If I turn the knob, then the wave form would be output on Pin A and B? but where does the power come from?

2)12 steps mean 12 sectors in one full revolution?

3)old A ,old B, A, B 4 bit word would give 16 values right?

- - - Updated - - -

table.png

why there's corresponding table with value of 0, -1 and 1 only?
 

chuckey said:
1) pin C
2) you have a 2 bit pattern(4 states) each repeated three times in one revolution
3) not 4 bit.
Your picture (table .prg) where does this fit in?
Frank
Click to expand...

1)Pin C is common pin tied to Ground. That's not power.
2)4 states. can this identity 12 sectored wheel? but I guess it also depend the A and B previous states right?
 

1. The encoder uses mechanical switches and doesn't need a power supply. It's your decision if you connect pin C to ground or a high level.
2. It's an incremental decoder, the output code is periodical with 120 degree. "12 steps" just says that 12 incremental steps make a full revolution, not that 12 positions can be identified.
 

The contact switches are grey codes in which only one contact will bounce at a time with 4 phases per 2 bit sector and 12 sectors per rev. each the same outputs separated by mechanical detent.

"If" you had another switch to indicate only 1 sector, you could have a 3 bit encoder and with a counter could decode 48 positions per revolution and a state machine for direction of motion and XOR 1 shot to compute velocity.

But normally these are just used for relative motion, direction and speed, not absolute position.

rot.jpg
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top