IC-MN_16 Datasheet, PDF (50/62 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
MT INTERFACE with EXTENDED FUNCTIONS
Rev F2, Page 50/62
The serial multiturn interface can be operated in the
BiSS C protocol which enables multiturn sensor error
messages to be evaluated (via the error and warning
bits, each of which are low active) and communica-
tion to be monitored (evaluation of the CRC bits, see
Figure 26).
SWC_MT
Code
0
1
Addr. 0x41; bit 6
CRC polynomial (HEX)
0x43
0x25
Table 91: MT Interface CRC polynomial
The error behavior of the multiturn interface has already
been described in Figures 21 and 22; only a set error
bit (low) or a CRC error are now also classified as a
communication error.
MODE_MT
Code
00
01
Notes
Addr. 0x40; bit 4:3
Function
Internal multiturn period counting
BiSS C protocol
If MODE_MT is altered during operation, command
SOFT_RES must be issued (see page 42).
Table 90: MT Interface operation mode
NCRC_MT
Code
0*
1
Note
Addr. 0x41; bit 4
Function
CRC verification active
Disabled
*) Only permitted with MODE_MT = 01.
Table 92: MT Interface CRC verification
MTMA
MTSLI
ACK START
MSB
LSB NERR NWRN MSB
LSB
DL_MT + SBL_MT
MT_ERR +
MT_WRN
CRC (NCRC_MT = 0)
tout
Figure 26: Example of the MT interface line signals with BiSS C protocol
Direct Communication To Multiturn Sensor
Making use of the BiSS Interface bus capabilities,
iC-MN can connect the external multiturn sensor to
the BiSS master controller when GET_MT is enabled.
To this end pin MA receiving the BiSS master’s clock
signal is fed through to pin MTMA and the MTSLI pin
is activated in place of the SLI pin. Upon enabling this
mode the singlecycle timeout must have elapsed and
an additional init command carried out by the BiSS mas-
ter, before it can run the first register communication.
the singleturn data. With GET_MT enabled, the exter-
nal multiturn can then be addressed via BiSS ID 0 and
the singleturn via BiSS ID 1. This temporal chain op-
eration eases device parameterization during encoder
manufacturing.
GET_MT
Code
0
1
Addr. 0x41; bit 5
Function
Disabled
MT sensor communication enabled
Example: external multiturn sensor built with iC-MN is ^{Table 93: Direct BiSS communication enable for MT}
connected to the MT interface of a first iC-MN, preparing
sensor via I/O Interface