Datasheet ADIS16485 (Analog Devices) - 2

ADIS16485 Silicon Anomaly Table 4. Incorrect Output Data String After Writing to FNCTIO_CTRL Register [er004] Background
The FNCTIO_CTRL register provides user configuration control for the digital input/output pins, and the TEMP_OUT register provides the internal temperature measurement, which serves as an input to the inertial calibration outputs.
Issue
On units that have firmware Revision 2.01 (or earlier), a write to the FNCTIO_CTRL register causes the TEMP_OUT variable to contain an incorrect value for 120 samples. Because this is an input to the calibration function for the gyroscopes and accelerometers, this causes the appearance of a discrete bias change between Sample 120 and Sample 121.
Workaround
When using units that have firmware Revision 2.01 (or earlier), ignore the first 120 samples of the output registers after writing to the FNCTIO_CTRL register. Use the FIRM_REV register to determine the firmware revision of a unit. For example, FIRM_REV = 0x0201 equates to a firmware revision of 2.01.
Related Issues
None.
Table 5. Incorrect Offset and Scale Correction Order [er005] Background
Each accelerometer and gyroscope has unique user-configurable offset and scale correction registers. For example, on the x-axis gyroscope, the XG_BIAS_HIGH and XG_BIAS_LOW registers combine to provide a 32-bit, twos complement bias (offset) correction factor, and the X_GYRO_SCALE register provides the scale correction function. The proper order of applying these correction factors is as follows: bias correction first, and scale correction second.
Issue
On units that have firmware Revision 2.01 (or earlier), the order of application is in reverse, where the ADIS16485 applies the scale correction value first, and then the offset value second.
Workaround
When using units that have firmware Revision 2.01 or earlier, be aware of this difference, if this function is part of system- level calibration processes. Use the FIRM_REV register to determine the firmware revision of a unit. For example, FIRM_REV = 0x0201 equates to a firmware revision of 2.01.
Related Issues
None.
Table 6. Factory Restore Command in GLOB_CMD[6] Not Working Properly [er006] Background
GLOB_CMD[6] provides a factory restore function that enables users to reset all user-configurable calibration registers to 0x0000 (factory default). To activate this function, turn to Page 3 by setting DIN = 0x8003, and then set GLOB_CMD[6] = 1 by writing the following two 16-bit commands to the DIN line: 0x8240 and 0x8300.
Issue
On units that have firmware Revision 2.03 (or earlier), setting GLOB_CMD[6] = 1 does not reset all of these registers.
Workaround
When using units with firmware Revision 2.03 (or earlier), write 0x0000 to each calibration register individually. Use the FIRM_REV register to determine the firmware revision of a unit. For example, FIRM_REV = 0x0203 equates to a firmware revision of 2.03.
Related Issues
None.
ANOMALY STATUS Reference Number Description Status Date Code
er001 Incorrect scale factors for the x_DELTANG_OUT and x_DELTANG_LOW registers Fixed 1226 er002 Incorrect scale factors for the x_DELTVEL_OUT and x_DELTVEL_LOW registers Fixed 1226 er003 Inaccurate TEMP_OUT readings Fixed 1226 er004 Incorrect output data string after writing to FNCTIO_CTRL register Fixed 1226 er005 Incorrect offset and scale correction order Fixed 1226 er006 Factory restore command in GLOB_CMD[6] not working properly Fixed 1314
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Rev. 0 | Page 2 of 2 Document Outline Performance Issues Anomaly Status