
preliminary
preliminary
iC-PVS
LINEAR/OFF-AXIS
BATTERY-BUFFERED ABSOLUTE POSITION HALL SENSOR
Rev A2, Page 40/51
Read Register
Opcode Register Read (0x81) is used to read data
from any number of consecutive registers in the on-chip
RAM.
!
For the access of an external I2C slave (e.g.
EEPROM), the opcode Read Register - I2C
Slave Access (0x97) must be used.
ADR
8 cycles
SCLK
MOSI
MISO
NCS
OP
OP
DATA1
...
DATA2
ADR
0x00
0x00
Figure 20: Register Read (Continuous)
As shown in Figure 20 the data stream to be sent on
MOSI consists of the opcode 0x81, followed by the
address of the first register to be read and a delay
byte 0x00. Those first three bytes are also transmit-
ted by iC-PVS on MISO, before sending the requested
data (DATA1) from the register at address (ADR). As
long as clock is sent and the slave stays active, data
(DATA2) from the next register at the incremented ad-
dress (ADR + 1) is transmitted. This procedure may be
continued for any number of consecutive registers.
Write Register
Opcode Write Register (0xCF) is used to write data
to any number of consecutive registers in the on-chip
RAM.
!
For the access of an external I2C slave (e.g.
EEPROM), the opcode Write Register - I2C
Slave Access (0xD2) must be used.
ADR
8 cycles
SCLK
MOSI
MISO
NCS
OP
OP
DATA1 DATA2
...
ADR
DATA1 DATA2
...
Figure 21: Register Write (Continuous)
As shown in Figure 21, the data stream to be sent on
MOSI consists of the opcode 0xCF, followed by the
address of the first register to be written and the data.
With each data byte appended the address of the reg-
ister to be written is incremented by one (ADR + 1). If
successfully received, the same data stream is trans-
mitted on MISO by iC-PVS. This procedure may be
continued for any number of consecutive registers as
long as clock is sent and the slave stays active (NCS =
low).
Read Position
Opcode Position Read (0xA6) is used to read the abso-
lute position data from iC-PVS.
SD1
8 cycles
SCLK
MOSI
MISO
NCS
OP
OP
SD2
...
REQ
Figure 22: Position Read
As shown in Figure 22, the position data is latched on
the first rising edge of SCLK when NCS is low (REQ).
The position data contains the complete absolute po-
sition data with optional configured error bit, warning
bit and optionally a sign-of-life counter (LC). The data
frame is concluded by a CRC checksum. All values are
transmitted MSB first an it is advised to read full bytes
for easy data handling. However iC-PVS also allows
to abort read-out of the absolute position data frame at
any point, e.g. skipping nERR/nWARN, LC, or CRC.
See chapter Absolute Data Format on page 26 for de-
tailed description of the absolute data format and con-
figuration options.
Write Command
Opcode Write Command (0xD9) writes values directly
to the device command register at address 0x77.
CMD
8 cycles
SCLK
MOSI
MISO
NCS
OP
OP
CMD
Figure 23: Write Command
The SPI master transmits the opcode Write Command
(0xD9) on MOSI, followed by the command to be exe-
cuted. The slave immediately outputs the opcode and
the command on MISO. Refer to chapter Commands
on page 46 for a list and description of available com-
mands.