1.
Overview
SSI-1016J
The SSI-1016J unit converts serial SSI data output by Temposonics sensors
to parallel data. SSI (Synchronous Serial Interface) is a serial
communication protocol developed and widely used in Europe. By
converting the SSI signal to a parallel signal with the SSI-1016J,
Temposonics sensors can be used with a wider variety of controllers.
Furthermore, the SSI-1016J provides the necessary clock signal for SSI
communication.
SSI Communication Protocol
The SSI protocol is a serial transmission over a 4-wire, RS422-compliant
wiring configuration. A clock pulse train from a controller is used to gate
out sensor data. One bit of position data is transmitted to the controller for
each clock pulse received by the sensor. The maximum SSI clock baud rate
is dependent on the cable length and a minimum of 16μs dwell time is
required between each clock pulse train.
The output data is formatted in either binary or gray code with either 24, 25,
or 26 bits of data depending on Temposonics sensor settings. The most
significant bit (MSB) comes first and the least significant bit (LSB)
represents the resolution specified by sensor specifications. Each bit is
transmitted synchronously with the rising edge of each clock pulse.
SSI-1016J Operation
The SSI-1016J unit interfaces with 24, 25, and 26 bit SSI Temposonics
sensors with no adjustment necessary and outputs parallel data via an open
collector output. The SSI-1016J has two operation modes which are
selectable via the rotary switch mounted on the SSI-1016 front panel.
2) SSI Clock
3) SSI Data (input)
4) Parallel Data (output)
1) Read Command
Data Ready Signal
Temposonics
Sensor
SSI-1016J
Controller
Figure 1
