ADIS16446

Data Sheet

Rev. 0 | Page 14 of 23

SYSTEM FUNCTIONS

GLOBAL COMMANDS

The GLOB_CMD register in Table 19 provides trigger bits

for software reset, flash memory management, and calibration

control. Start each of these functions by writing a 1 to the assigned

bit in the GLOB_CMD register. After completing the task, the

bit automatically returns to 0. For example, set GLOB_CMD, Bit 7

= 1 (DIN = 0xBE80) to initiate a software reset. Set GLOB_CMD,

Bit 3 = 1 (DIN = 0xBE08) to back up the user register contents

in the nonvolatile flash. This sequence includes loading the

control registers with the data in their respective flash memory

locations prior to producing new data.

Table 19. GLOB_CMD (Base Address = 0x3E), Write Only

Bits

Description (Default = 0x0000)

[15:8]

Not used

7

Software reset

[6:4]

Not used

3

Flash update

2

Not used

1

Factory calibration restore

0

Gyroscope bias correction

Flash Update

When using the user calibration registers to optimize system

level accuracy, set GLOB_CMD, Bit 3 = 1 (DIN = 0xBE04) to save

these settings in the nonvolatile flash memory. Be sure to consider

the endurance rating of the flash memory when determining how

often to update the user correction factors in the flash memory.

Restoring Factory Calibration

Set GLOB_CMD, Bit 1 = 1 (DIN = 0xBE02) to execute the

factory calibration restore function, which resets the gyroscope

and accelerometer offset registers to 0x0000 and all sensor data to

0. Restoring the factory calibration automatically updates the

flash memory and restarts sampling and processing data. See

Table 19 for information on GLOB_CMD.

PRODUCT IDENTIFICATION

The PROD_ID register in Table 22 contains the binary equivalent

of 16,446. This register provides a product specific variable for

systems that must track this in their system software. The

LOT_ID1 and LOT_ID2 registers in Table 20 and Table 21

combine to provide a unique, 32-bit lot identification code.

The SERIAL_NUM register in Table 23 contains a binary

number that represents the serial number on the device label.

The assigned serial numbers in SERIAL_NUM are lot specific.

Table 20. LOT_ID1 (Base Address = 0x52), Read Only

Bits

Description

[15:0]

Lot identification, binary code

Table 21. LOT_ID2 (Base Address = 0x54), Read Only

Bits

Description

[15:0]

Lot identification, binary code

Table 22. PROD_ID (Base Address = 0x56), Read Only

Bits

Description (Default = 0x403E)

[15:0]

Product identification = 0x403E. Note that 0x403E

equals 16,446 decimal.

Table 23. SERIAL_NUM (Base Address = 0x58), Read Only

Bits

Description

[15:12]

Reserved

[11:0]

Serial number, 1 to 4094 (0xFFE)

SELF-TEST FUNCTION

The MSC_CTRL register in Table 24 provides a self test function

for the gyroscopes and accelerometers. This function allows the

user to verify the mechanical integrity of each MEMS sensor.

When enabled, the self test function applies an electrostatic force

to each internal sensor element which causes them to move. The

movement in each element simulates its response to actual rotation

and/or acceleration and generates a predictable electrical response

in the sensor outputs. Set MSC_CTRL, Bit 10 = 1 (DIN = 0xB504)

to activate the internal self test routine, which compares the

response to an expected range of responses and reports a pass

or fail response to DIAG_STAT, Bit 5. If this is high, review

DIAG_STAT, Bits[15:10] to identify the failing sensor.

Table 24. MSC_CTRL (Base Address = 0x34), Read/Write

Bits

Description (Default = 0x0006)

[15:12]

Not used, always set to 0000

11

1 = enabled, 0 = disabled

10

1 = enabled, 0 = disabled

[9:7]

Not used. Always set to 000

6

Point of percussion, see Figure 21

1 = enabled, 0 = disabled

[5:3]

Not used, always set to 000

2

Data ready enable

1 = enabled, 0 = disabled

1

Data ready polarity

1 = active high when data is valid

0 = active low when data is valid

0

Data ready line select

1 = DIO2, 0 = DIO1

1

Bit 11 and Bit 10 are automatically reset to 0 after finishing their respective tests.