IC-MN_16 Datasheet, PDF (51/62 Pages) IC-Haus GmbH – 25-BIT NONIUS ENCODER WITH 3-CH. SAMPLING 13-BIT Sin/D INTERPOLATION

iC-MN 25-BIT NONIUS ENCODER
WITH 3-CH. SAMPLING 13-BIT Sin/D INTERPOLATION
PRESET FUNCTION
Rev F2, Page 51/62
The preset function sets the output position data to a
predefined position value and is initiated by a high flank
at pin PRES or by calling the SOFT_PRES command
(writing 0x02 to the command register, see Table 70).
If an external EEPROM is available the preset values
are read in from the preset registers. A preset value of
zero is otherwise assumed. The current position is de-
termined. Correction factors for the output (OFFS_ST,
OFFS_MT) are calculated and stored in the internal
RAM. With an EEPROM available the entire contents
of the RAM are written to said EEPROM, thus storing
the OFFS_ST and OFFS_MT data.
Note:
Command SOFT_PRES and function of pin PRES
blocks iC-MN’s internal RAM for accesses over a cer-
tain time. During this time register operation via the
BiSS interface the address will be dismissed and bit
CMD_EXE of the status register is valid.
PRES_ST
0x00000
...
0x7FFFF
Addr. 0x54; bit 6:0
Addr. 0x53; bit 7:0
Addr. 0x52; bit 7:0
Addr. 0x51; bit 7:0
Addr. 0x50; bit 7:0
Preset register singleturn (EEPROM only, see text)
Table 95: Preset value for ST data output
The position of the preset value for the singleturn data
word (ST_DW) in preset register PRES_ST varies de-
pending on the converter mode (MODE_ST see Table
42). For nonius synchronization operating mode see
Figure 27; see Figure 28 for multiturn synchronization
operating mode.
In the PRES_MT register the multiturn preset values
are always justified to the right with the LSB (starting at
address 0x55, bit 0).
ATTENTION!
During the preset sequence wait time it must be en-
sured that the supply voltage to the two devices iC-MN
and the EEPROM is maintained. If this is not the case,
on the next system start-up the whole configuration
parameters will be recognized as being faulty and this
will trigger the setting of the error bit (EPR_ERR) in
the status register!
OFFS_MT
0x000
...
0xFFF
Addr. 0x37; bit 7:0
Addr. 0x36; bit 7:0
Addr. 0x35; bit 7:0
Multiturn output offset
Table 96: Position offset for MT data output
For the output the OFFS_ST and OFFS_MT values are
subtracted from the internal synchronized result with
each conversion.
Note:
In MODE_ST = 0x05-0x07 and 0x0D the sensor data
is designated faulty after the first readout. The readout
data is equivalent to the correction factor.
OFFS_ST
0x00000
...
0x7FFFF
Addr. 0x34; bit 6:0
Addr. 0x33; bit 7:0
Addr. 0x32; bit 7:0
Addr. 0x31; bit 7:0
Addr. 0x30; bit 7:0
Singleturn output offset
Table 94: Position offset for ST data output
PRES_MT
0x000
...
0xFFF
Addr. 0x57; bit 7:0
Addr. 0x56; bit 7:0
Addr. 0x55; bit 7:0
Preset register multiturn (EEPROM only)
Table 97: Preset value for MT data output
physical
resolution:
up to 12 bit period-information
UBL_S+UBL_N
up to 13 bit master-information
UBL_M
MSB
period
LSB
period
MSB
master
LSB
master
PRES_ST
register:
0
0
0
MSB
ST_DW
LSB
ST_DW
0
0
0
0
0
ADR 0x54
bit 6
ADR 0x53
bit 3
ADR 0x53
bit 2
datalength defined by DL_ST
ADR 0x51
bit 6
Figure 27: PRES_ST with nonius synchronization
mode