Operating instructions

Absolute Rotary Encoders
58
Absolute Encoders AVS58/AVM58 Series
Pepperl+Fuchs Inc. • 1600 Enterprise Parkway • Twinsburg, Ohio 44087-2245 • www.am.pepperl-fuchs.com
Telephone [phone] • FAX [phone] • E-Mail: [e-mail]
®
PEPPERL+FUCHS
Programming
Description
The synchronous serial interface was specially developed for transferring the output
data of an absolute encoder to a control device. The control module sends a clock
signal and the absolute encoder responds with the position value.
Thus only 4 lines are required for the clock and data, regardless of the rotary encoder
resolution. The RS-422 interface is galvanically isolated from the power supply.
LSB
MSB
T
p
T
m
T
Clo
SSI Data Transfer
ck
Data
D
n
D
n-1
D
n-2
D
n-3
D
2
D
1
S
D
1
, ..., D
n
: Position data T = 1/f: Duration of period, f ≤ 1 MHz
S: Special bit T
m
: Monoflop time 10-30 µs
MSB: Most significant bit T
p
: Clock pause ≥ monoflop time (T
p
≥ T
m
)
LSB: Least significant bit
Rotary encoder AV
®
Interface electronics
Receiver
Tr ansceiver
RS 422
Tr
Block Diagram
ansceiver
RS 422
Logic
opt./galv.
separation
Clock
generator
Data +
Data -
Clock -
Clock +
Line length in m Baud rate in kHz
<50 <400
<100 <300
<200 <200
<400 <100
Line Length