Rockwell Automation 1771-DE Absolute Encoder Module User Manual - Manual (Page 34)

Offset Programming
Chapter 5
5Ć3
Format of Offset Words
5 17 16 15 14 13 12 11 10 7 6 4 3 2 1 0
S OFFSET VALUE
NO. OF ENCODER POSITIONS
The offset words are the last two words of the write-data block that you send
to the absolute encoder module.
If you are controlling
2 outputs
4 outputs
6 outputs
8 outputs
The offset words are:
words 6 and 7
words 11 and 12
words 16 and 17
words 21 and 22
S = sign bit. Set this bit if the offset has a negative value; reset the bit if
the offset has a positive value.
Bit #
13523
The first offset word contains the value of the offset. Bit 17 of this word
is the sign bit. It indicates whether the offset is negative or positive. Set
bit 17 if the offset is negative; reset it if the offset is positive.
The second offset word is the number of positions of the encoder. If you
are using a 0 to 4,095-position encoder, your second offset word is 4,096.
BlockĆtransferĆwrite Data with Offset
The number of words you send to the module depends on the number of
outputs the module controls. The offset feature adds two words to the
total number of words you send to the module:
If the module
controls:
You send:
2 outputs 7 words
4 outputs 12 words
6 outputs 17 words
8 outputs 22 words
If the module is controlling eight outputs, your block-transfer-write data
now looks like this: