ADIS16480/PCBZ Analog Devices, ADIS16480/PCBZ Datasheet - Page 11

• Manufacturer Part Number: ADIS16480/PCBZ
• Description: Acceleration Sensor Development Tools ADIS16480/PCB EVAL. BD. PB Free
• Manufacturer: Analog Devices

Specifications of ADIS16480/PCBZ

• Rohs: yes
• Tool Is For Evaluation Of: ADIS16480
• Acceleration: 18 g
• Interface Type: SPI
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Current: 254 mA
• Factory Pack Quantity: 1

Data Sheet
SPI COMMUNICATION
The SPI port supports full duplex communication, as shown in
Figure 17, which enables external processors to write to DIN
while reading DOUT, if the previous command was a read
request. Figure 17 provides a guideline for the bit coding on
both DIN and DOUT.
DEVICE CONFIGURATION
The SPI provides write access to the control registers, one byte at
a time, using the bit assignments shown in Figure 17. Each register
has 16 bits, where Bits[7:0] represent the lower address (listed in
Table 9) and Bits[15:8] represent the upper address. Write to the
lower byte of a register first, followed by a write to its upper
byte. The only register that changes with a single write to its
lower byte is the PAGE_ID register. For a write command, the
first bit in the DIN sequence is set to 1. Address Bits[A6:A0]
represent the target address, and Data Command
Bits[DC7:DC0] represent the data being written to the location.
Figure 13 provides an example of writing 0x03 to Address 0x00
(PAGE_ID [7:0]), using DIN = 0x8003. This write command
activates the control page for SPI access.
Dual Memory Structure
Writing configuration data to a control register updates its SRAM
contents, which are volatile. After optimizing each relevant control
register setting in a system, use the manual flash update command,
which is located in GLOB_CMD[3] on Page 3 of the register map.
Activate the manual flash update command by turning to Page 3
(DIN = 0x8003) and setting GLOB_CMD[3] = 1 (DIN = 0x8208,
then DIN = 0x8300). Make sure that the power supply is within
specification for the entire 1100 ms processing time for a flash
memory update. Table 9 provides a memory map for all of
the user registers, which includes a column of flash backup
information. A yes in this column indicates that a register
has a mirror location in flash and, when backed up properly,
automatically restores itself during startup or after a reset.
Figure 14 provides a diagram of the dual memory structure
used to manage operation and store critical user settings.
SCLK
DIN = 1000 0000 0000 0011 = 0x8003, WRITES 0x03 TO ADDRESS 0x00
Figure 13. SPI Sequence for Activating the Control Page (DIN = 0x8003)
DIN
CS
DOUT
NOTES
1. DOUT BITS ARE PRODUCED ONLY WHEN THE PREVIOUS 16-BIT DIN SEQUENCE STARTS WITH R/W = 0.
2. WHEN CS IS HIGH, DOUT IS IN A THREE-STATE, HIGH IMPEDANCE MODE, WHICH ALLOWS MULTIFUNCTIONAL USE OF THE LINE
SCLK
DIN
FOR OTHER DEVICES.
CS
D15
R/W
D14
A6
D13
A5
D12
A4
D11
A3
D10
A2
Figure 17. SPI Communication Bit Sequence
A1
D9
A0
D8
Rev. A | Page 11 of 44
DC7 DC6 DC5 DC4 DC3 DC2 DC1 DC0
D7
D6
D5
READING SENSOR DATA
The
data register access. Write 0x00 to the PAGE_ID register (DIN =
0x8000) to activate Page 0 for data access after accessing any other
page. A single register read requires two 16-bit SPI cycles. The
first cycle requests the contents of a register using the bit assignments
in Figure 17, and then the register contents follow DOUT during
the second sequence. The first bit in a DIN command is zero,
followed by either the upper or lower address for the register.
The last eight bits are don’t care, but the SPI requires the full set
of 16 SCLKs to receive the request. Figure 15 includes two register
reads in succession, which starts with DIN = 0x1A00 to request
the contents of the Z_GYRO_OUT register and follows with
0x1800 to request the contents of the Z_GYRO_LOW register.
Figure 16 provides an example of the four SPI signals when reading
PROD_ID in a repeating pattern. This is a good pattern to use
for troubleshooting the SPI interface setup and communications
because the contents of PROD_ID are predefined and stable.
DOUT
SCLK
DIN
CS
D4
ADIS16480
DOUT
DIN
DOUT = 0100 0000 0110 0000 = 0x4060 = 16,480 (PROD_ID)
D3
(NO SPI ACCESS)
Figure 16. SPI Read Example, Second 16-Bit Sequence
FLASH MEMORY
NONVOLATILE
D2
Figure 14. SRAM and Flash Memory Diagram
automatically starts up and activates Page 0 for
0x1A00
D1
Figure 15. SPI Read Example
D0
START-UP
MANUAL
BACKUP
FLASH
RESET
Z_GYRO_OUT
0x1800
DIN = 0111 1110 0000 0000 = 0x7E00
D15
R/W
D14
A6
SPI ACCESS
VOLATILE
Z_GYRO_LOW
SRAM
ADDRESS
D13
A5
NEXT
ADIS16480