IC-MH_17 Datasheet, PDF (21/26 Pages) IC-Haus GmbH – 12-BIT ANGULAR HALL ENCODER

iC-MH
12-BIT ANGULAR HALL ENCODER
Rev C2, Page 21/26
mode it is not possible to vary the parameter set. The
data is transmitted as reduced Gray code, e.g. after
converting into binary code, the data range is symmet-
rical to the center of the number string. For example,
with a set resolution of 360 data values between 76 and
435 are transmitted.
Figure 24: SSI protocol, data GRAY-coded
The register range 0x00 to 0x0F is equivalent to the set-
tings with which the IC can be parameterized. The set-
tings directly affect the corresponding switching parts.
It is important to note that test register 0x0E can only be
written to when pin VZAP is connected to VPD. When
VPD > 6 V, write access to the test register is ignored.
Register 0x0F can be configured at potentials V(VZAP)
> Vt(VZAP)hi.
The register range 0x10 to 0x1F is read-only and re-
flects the contents of the integrated zapping diodes.
Following programming the data can be verified via
these addresses. After the supply voltage is connected,
the contents of the zapping diodes are copied to the
RAM area 0x00 to 0x0F. Then the settings can be
overwritten via the BiSS interface. Overwriting is not
possible if the CFGPROT bit is set.
Errors in the module are signaled via the error message
output NERR. This open-drain output signals an error if
the output is pulled against VND. If the error condition
no longer exists, then the pin is released again after
a waiting time of approximately 1 ms. If the integrated
pull-up resistor is deactivated with DPU = ’1’, then an
external resistor must be provided. With DPU = ’0’ it
brings the pin up to the high level again.
DPU
0
1
Addr. 0x04; bit 6
Pull-up activated
Pull-up deactivated
the transmitted sensor data in accordance with the set
resolution. The sensor data is transmitted right-justified
and filled with preceding zeros on smaller resolutions
than 12 bit. The following table shows the data length
according to the resolution.
DLEN
2
3
4
5
6
7
8
9
10
11
12
Addr. 0x43; bit 3:0
CFGRES = ’00000000’, 4
CFGRES = ’00000001’, 8
CFGRES = ’0000001x’, 12 to 16
CFGRES = ’000001xx’, 20 to 32
CFGRES = ’00001xxx’, 36 to 64
CFGRES = ’0001xxxx’, 68 to 128
CFGRES = ’001xxxxx’, 132 to 256
CFGRES = ’01xxxxxx’, 260 to 512
CFGRES = ’10000000’, 1024
CFGRES = ’10000001’, 2048
CFGRES = ’10000010’, 4096
Table 30: Data length
N.B. With CFGRES = ’10000010’, 4096 and using
BiSS protocol the device provides a BiSS Profile ID
0x2C 0x0C (0x2C in address 0x42 and 0x0C in ad-
dress 0x43) that is "BiSS Profile BP1 Standard Rotary
Encoder" conform.
The status register provides information on the status
of the module. There are 5 different errors that can be
signaled. Following unsuccessful programming of the
zapping diodes, the bit PROGERR is set. If an attempt
is made to read the current position via the BiSS In-
terface during the startup phase, an error is signaled
with ERRSDATA, as the actual position is not yet avail-
able. The ERRAMAX bit is output to signal that the
amplitude is too high, while the ERRAMIN bit signals
an amplitude which is too low, caused, for example, by
too great a distance to the magnet. If the NERR pin
is pulled against VND outside the module, this error is
also signaled via the BiSS Interface on the low active
status flag nERR in the SCD. The ERREXT bit is then
equal to ’1’. The error bits are reset again after the
status register is read out at the address 0x77. The
error bit in the data word is then also read in the next
cycle as ’0’.
Table 29: Activation of NERR pull-up
With the BiSS profile ID, the data format of the sensor
can be requested. Reading the BiSS profile ID results
0x2C in address 0x43, which identifies BiSS Profile BP1
and two most significant bits of the multiturn resolution,
what is here always ’00’. Reading the register 0x43
contains the three least significant bits of the multiturn
resolution, what is here always ’000’ and five bits of
the singleturn resolution as is the data length DLEN of
CFGTOS
0
1
x
CFGTOB
0
0
1
Timeout
16 µs
2 µs
2 µs
Table 31: BiSS timeout for sensor data (SCD)
The BiSS timeout can be programmed to a shorter
value with the CFGTOS bit. However, this setting is
reset to the default value 16 µs again following a reset.