ADIS16255/PCBZ Analog Devices Inc, ADIS16255/PCBZ Datasheet - Page 11

• Manufacturer Part Number: ADIS16255/PCBZ
• Description: BOARD EVAL FOR ADIS16255
• Manufacturer: Analog Devices Inc
• Series: iMEMS®, iSensor™r

Specifications of ADIS16255/PCBZ

• Sensor Type: Gyroscope, 1 Axis (Yaw Rate)
• Sensing Range: ±80°/sec, ±160°/sec, ±320°/sec
• Interface: SPI Serial
• Sensitivity: 0.018°/sec/LSB
• Voltage - Supply: 4.75 V ~ 5.25 V
• Embedded: No
• Utilized Ic / Part: ADIS16255
• For Use With: ADISUSBZ - KIT EVAL ADIS W/SOFTWARE USBADISEVALZ - KIT PC EVALUATION W/SOFTWARE
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

BASIC OPERATION
The ADIS16250/ADIS16255 are designed for simple integration
into industrial system designs, requiring only a 5.0 V power
supply and a 4-wire, industry standard serial peripheral interface
(SPI). All outputs and user-programmable functions are handled
by a simple register structure. Each register is 16 bits in length
and has its own unique bit map. The 16 bits in each register
consist of an upper (D8 to D15) byte and a lower (D0 to D7)
byte, each of which has its own 6-bit address.
SERIAL PERIPHERAL INTERFACE (SPI)
The ADIS16250/ADIS16255 serial peripheral interface (SPI)
port includes four signals: chip select ( CS ), serial clock (SCLK),
data input (DIN), and data output (DOUT). The CS line enables
the ADIS16250/ADIS16255 SPI port and frames each SPI event,
which consists of single or multiple data frames. When this signal is
high, the DOUT lines are in a high impedance state and the signals
on DIN and SCLK have no impact on operation. A complete
data frame contains 16 clock cycles. Because the SPI port operates
in full duplex mode, it supports simultaneous, 16-bit receive (DIN)
and transmit (DOUT) functions during the same data frame.
Refer to Table 2, Figure 2, and Figure 3 for detailed timing and
operation of the SPI port.
W/R BIT
DOUT
SCLK
SCLK
DIN
CS
DIN
CS
DON’T
CARE
WRITE = 1
READ = 0
W/R
BASED ON PREVIOUS COMMAND
ZERO
ADDRESS
A5
DATA FRAME
REGISTER ADDRESS
A4
Figure 21. SPI Sequence for Read Commands
A3
A2
Figure 20. DIN Bit Sequence
DON’T CARE
Rev. D | Page 11 of 20
A1
DATA FRAME
A0
DC7
Writing to Registers
Figure 20 displays a typical data frame for writing a command
to a control register. In this case, the first bit of the DIN sequence is
a 1, followed by a 0, the 6-bit address, and the 8-bit data command.
Because each write command covers a single byte of data, two
data frames are required when writing the entire 16-bit space of a
register.
Reading from Registers
Reading the contents of a register requires a modification to the
sequence in Figure 20. In this case, the first two bits in the DIN
sequence are 0, followed by the address of the register. Each register
has two addresses (upper, lower), but either one can be used to
access its entire 16 bits of data. The final eight bits of the DIN
sequence are irrelevant and can be counted as don’t cares during a
read command. During the next data frame, the DOUT sequence
contains the register’s 16-bit data, as shown in Figure 21.
Although a single read command requires two separate data
frames, the full duplex mode minimizes this overhead, requiring
only one extra data frame when continuously sampling.
DON’T CARE FOR READ COMMANDS
DC6
DATA FOR WRITE COMMANDS
DC5 DC4
16-BIT REGISTER CONTENTS
DATA FRAME
NEXT COMMAND
DC3 DC2 DC1
ADIS16250/ADIS16255
DC0
DON’T
CARE