Jetter JetWeb JX2-CNT1, Руководство пользователя

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JX2-CNT1 11 SSI Absolute Encoder
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Example 5
Like example 1. But the encoder appends 3 special bits after the position bits.
Therefore, 13 clocks are required. The special bits are taken into account when the
position value is evaluated. The user must arrange for separation of special bits from
the position value in the application program by programming masked reading and
restoring the original position value as a result of right shift by the corresponding
number of places.
Example 6
In this example, 10 position bits are transmitted right-justified with a rate of 25 clocks.
The leading zero bits entered into register 3xx0 have no effect on the transmitted
position value. Even deletion of the most significant bit, which has been read in cycle
1, has not effect on the position value. Position range displayed in register 3xx0: 0 ...
1023 (in steps of 1).
Example 7
Like example 6, however with parity bit and parity check enabled.
Example 8
In this example, 10 position bits are read out left-justified with a rate of 25 clocks.
Instead of placing the zero bits before the position bits, like in example 6, they are
appended after the position bits. This results in a significant change in the position
range, as the 10 position bits are shifted to the left by several binary places
(depending on the number of inserted zero bits). As the value has been read out at
25 clocks and only the lowest 24 bits can be taken over, the highest bit, which has
been read out in clock 1, gets lost. Position range displayed in register 3xx0: -
8.388.608 ... + 8,388,607 in steps of 32,768. However, it is also possible to reduce
the number of clocks, and to do without reading out the trailing zero bits. Thus, the
position values remains at the correkt binary location.
Example 9
Like example 8, however with 2 special bits appended. To evaluate the data proceed
according to example 5.
Example 10
In this example, 10 position bits are read out in fir-tree format with 24 clocks. The
leading zero bits do not have an effect on the position value. But the appended zero
bits shift the position bits upwards by several binary places, like in example 8. This
has an significant effect on the position range. Position range displayed in register
3xx0: - 32.768 ... + 32,767 in steps of 128. However, it is also possible to reduce the
number of clocks, and to do without reading out the trailing zero bits. Thus, the
position values remains at the correkt binary location.
Example 11
Like example 10, but with one additional clock due to the parity bit and parity check.
Example 12
Like example 11, however without parity check, Furthermore, a special bit is sent
instead of the parity bit. Due to the 25 clocks, the zero bit, which has been read out
in cycle 1, is not taken into account when generating the position value. However, the
special bit is included in the position value. To separate the special bit from the
position value proceed according to example 5.