Lika MRA, Руководство пользователя

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SMRA - SSI and BiSS
After having entered a value next to the
Preset
registers you can either save it
without activating the preset function or both save and activate it at the same
time. Use the
Save parameters
function (set “01” in the
Command
register) to
save the new Preset value without activating it.
Use the
Save parameters and activate Preset
function (set “02” in the
Command
register) to both save and activate the new Preset value.
The max. allowed Preset value depends on the resolution of the device:
resolution = 12 bits
 max preset = 0F FFh
resolution = 13 bits  max preset = 1F FFh
resolution = 14 bits  max preset = 3F FFh
Default =
00 00h
.
Min. Value = 00 00h
Max. value = according to resolution
NOTE
We suggest setting the preset when the ring is not rotating.
Preset register structure:
Register 12 13
LSB MSB
2
7
- 2
0
2
15
- 2
8
NOTE
The Preset value must be expressed in a 16-bit format, thus the Preset value you
want to set must be adjusted by multiplying it by the factor 2
16-nbit
, where nbit is
the number of bits relating to the resolution of the encoder. See the following
example.
PRESET SETTING EXAMPLE
In a 14-bit resolution encoder (2 14 = 16,384 information), you want to set the
following
Preset
value = 10,000
10
.
1. As previously stated, first of all you must enable the setting of the Preset
registers by entering the value “01” next to the
Preset setting enable
register.
2. Then multiply the desired preset value (10,000
10
) by the factor 2 16-nbit , i.e. 2 2
(16 – 14 = 2).
Thus the
Preset
value to be set in the registers will be:
10,000
10
* 2 16-14 = 40,000
10
= 9C 40 hex.
3. Then, before saving the entered data, set the value “00” next to the
Preset
setting enable
register.
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