Copley Controls Accelnet Plus BEL Series User Manual page 105

Accelnet & Stepnet Plus Panels User Guide
SSI A E
BSOLUTE
The SSI (Synchronous Serial Interface) is an interface used to connect an absolute position encoder to a
motion controller or control system. The drive provides a train of clock signals in differential format to the
encoder which initiates the transmission of the position data on the subsequent clock pulses. The polling of
the encoder data occurs at the current loop frequency (16 kHz). The number of encoder data bits and counts
per motor revolution are programmable. The hardware bus consists of two signals: SCLK and SDATA. Data is
sent in 8 bit bytes, LSB first. The SCLK signal is only active during transfers. Data is clocked out on the falling
edge and clock in on the rising edge of the Master.
B SS A
I BSOLUTE
BiSS is an Open Source digital interface for sensors and actuators. BiSS refers to principles of well known
industrial standards for Serial Synchronous Interfaces like SSI, AS-Interface® and Interbus® with additional
options.
Serial Synchronous Data Communication
Cyclic at high speed
2 unidirectional lines Clock and Data
Line delay compensation for high speed data transfer
Request for data generation at slaves
Safety capable: CRC, Errors, Warnings
Bus capability incl. actuators
Bidirectional
BiSS B-protocol: Mode choice at each cycle start
BiSS C-protocol: Continuous mode
NCODER
E
NCODER
16-01339 Rev 07