Lenze I/O system 1000 System Manual - Manual (Page 456)

PROFIBUS communication
Parameterising the encoder evaluation
SSI − EPM−S604
9
l
456 EDSIO1000 EN 7.0
Lenze Description/value Name Data set Lenze Description/value Name
Byte No.
5 Bit 1 ... 0: Ready for operation
During "Monitoring operation" the module serves to
monitor the data exchange between an SSI master and
an SSI encoder. It receives the cycle by the master and
the data flow by the SSI encoder.
In the "Master mode" operating mode the module
provides a cycle to the encoder and receives data by the
encoder.
01
b
= monitoring operation
10
b
= master mode
Bit 2: Shifting direction
Specify the orientation of the encoder data here. More
information can be found in the data sheet for your
encoder. Usually, the SSI encoder uses "MSB first".
0 = LSB first (LSB is transmitted first)
1 = MSB first (MSB is transmitted first)
Bit 3: edge clock signal
Here you can specify the edge type of the clock signal,
in the case of which the encoder supplies data.
Information on this can be found in the data sheet for
your encoder. Usually the SSI encoders respond to
rising edges.
0 = falling edge
1 = rising edge
Bit 4: Coding
In the "Binary code" setting, the provided encoder
value remains unchanged. In the "Gray code" setting,
the gray−coded value provided by the encoder is
converted into a binary value. Only after this
conversion, the received encoder value is scaled, if
required. The Gray code is another form of
representation of the binary code. It is based on the
fact that two adjacent Gray numbers differ from each
other in exactly one bit. If the Gray code is used,
transmission errors can be easily detected, since
adjacent characters must only differ from each other in
one digit. Information on this can be found in the data
sheet for your encoder.
0 = standard code
1 = Gray code
Bits 7 ... 5: reserved
1E
h
6 Reserved
7 SSI function By enabling the SSI function the module starts with the
cycle output and the evaluation of the encoder data. In the
"monitor operation" mode, the module starts with the
encoder evaluation.
0 (00
h
) = inhibited
1 (01
h
) = enabled
00
h