iC-MN 25-BIT NONIUS ENCODER
WITH 3-CH. SAMPLING 13-BIT Sin/D INTERPOLATION
Rev D1, Page 33/59
S/D CONVERSION with MULTITURN SYNCHRONIZATION
In multiturn modes the output data word always Op. Mode Descriptions Of Multiturn Modes
matches the current converted and synchronized track
data. For 1 to 3 selected tracks parameters SBL_S and
SBL_N adjust the gear box synchronization, whereas MODE_ST Code 0x0C
the selected used bit lengths (UBL_x) determine the The processing time is largely determined by the sum
reduction ratio required for the multiturn gear box:
of the conversion time of the configured tracks. Proce-
dure of conversion:
Synchronization
Gear reduction
2UBL_M
Master track ↔ Singleturn
Segment track ↔ Master track
Nonius track ↔ Segment track
1. A data readout request triggers the complete
conversion of the set tracks
2UBL_S
2UBL_N
2. Gear box synchronization
One limitation in multiturn mode is that neither an ex-
ternal multiturn can be configured nor counted mul-
titurn data output. Parameters MODE_MT and M2S
must be set to 0. Figure 12 shows the synchronization
principle, where ϕ represents the digitized angle of the
relevant track.
3. Transmission of the output data
MODE_ST Code 0x0D
The processing time is low as ”old” data is transmitted,
the time of sampling is, however, known. The conver-
sion procedure is as follows:
1. With a data readout: immediate transmission of
the data from the last readout cycle
2. With a data readout: start of a new conversion
and providing of data for the next readout cycle.
NB: The data from the first readout is invalid following
a SOFT_RES.
MODE_ST Code 0x0E
The processing time is low and the time of sampling
not precisely known. The conversion procedure is as
follows:
Figure 12: Principle of multiturn synchronisation
1. Regardless of the data readout: permanent
background conversion
MODE_ST
Addr. 0x3D; bit 7:4
Operation modes with multiturn synchronization (MT Modes)
Code
0x0C
Description
2. With a data readout: transmission of current
data.
Data output following S/D conversion of all tracks
with MT synchronization configured via SBL_x
Data output: result of previously triggered S/D
conversion
MODE_ST Code 0x0F
0x0D
0x0E
with MT synchronization configured via SBL_x
This mode can be used in systems which require that
asynchronous sampling is independent of the data
readout timing. The conversion procedure is as fol-
lows:
Data output: last result of background S/D
conversion (asynchronous)
with MT synchronization configured via SBL_x
Data output: last result of S/D conversion triggered
by pin T3
0x0F
with MT synchronization configured via SBL_x
1. A conversion is triggered via pin T3, if applicable
with gear box code synchronization.
Notes
On changing parameter MODE_ST during
operation command SOFT_RES should be issued.
2. With a data readout the most recent output data
triggered by pin T3 is transmitted.
Table 47: Multiturn modes
ICHAUS [ IC-HAUS GMBH ]
