
AD5100
Rev. A | Page 28 of 36
TEMPORARY OVERRIDE OF DEFAULT SETTINGS
Even with OTP-Programmed parts, it is possible to temporarily
override the default values of any of the permanently program-
mable registers. To override a permanent setting in a particular
register (when the lock bit is programmed), the following sequence
should be used:
1.
Set Bit 3 = 1 in Register 0x16 (special function 1).
2.
Write the desired temporary data to the register of choice.
While the override bit (Bit 3) is set in Register 0x16, the user
can override any registers by simply writing to them with new data.
To reset an overridden register to its default setting, the
following sequence should be used:
1.
Set Bit 3 = 0 in Register 0x16.
2.
Write a dummy byte to the register of choice.
Clearing the override bit in Register 0x16 does not cause all
overridden registers to revert to their defaults at the same time.
For example, imagine that the user overrides Register 0x01,
Register 0x02, and Register 0x03.
If the user subsequently clears the override bit in Register 0x16
and writes a dummy byte to Register 0x01, Register 0x01 reverts
to its default value. However, Register 0x02 and Register 0x03
still contain their override data. To revert both registers to their
default values, the user must write dummy data to each register
individually.
Power cycling the AD5100 also resets all registers to their
programmed defaults.