IX34208a_e.doc / Aug-09
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With Master operation, therefore other settings will result in generation of the next upper or
lower value according to above list. With all settings <250.0 kHz the error between set rate and
generated rate becomes negligible.
It is mandatory to set the Baud rate also with Slave operation. In this case, however, the
setting serves only to determine the pause time for correct synchronization (pause is detected
after 4 clock cycles). The unit automatically synchronizes with every remote clock signal within
the specified Baud rate range.
x
Where with Master operation your encoder uses another bit number than 13, 21 or 25,
please select the next higher number (e.g. 21 with a 16 bit encoder)
.
x
With Slave operation the unit works fine only if the associated Master generates
telegrams with lengths of either 13 or 21 or 25 clocks. The unit is unable to handle
different telegram lengths when used in Slave Mode.
x
Unused Bits may, but excessive Bits must be blanked by corresponding setting of
parameters „Hi_bit“ and „Lo_bit“. For successful use of the bit blanking function it is
important to observe the relevant hints given under chapter 5.2 !
5.2. Evaluation of Encoder Bits
This chapter explains the correlation between the Basic Parameter „„BitS“ and the Operational
Parameters „„Hi bit“ and „„Lo bit“. The example below uses an encoder with 16 bits.
Basic Settings:
With a 16 bit encoder the Basic Parameter „BitS“ can be set to 21 (or also to 25). This example
uses the setting "BitS“= 21 (with 25 all explanations would apply correspondingly). With every
telegram the unit will now request always 21 bits from the encoder. The encoder itself however
will return 16 usable bits only followed by 5 waste bits. Basically all telegrams start with the
most significant bit (MSB) and close with the least significant bit (LSB). The unusable waste
bits (X) will follow at the tail end. If we would want to evaluate all of the 16 usable bits, we
consequently would need to set „Hi bit“ to 21 and „Lo bit“ to 6.
Hi Bit
Î
Lo Bit
Î
Requested
Bits (Clocks)
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Usable Bits
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
X
X
X
X
X
