at42qt1481 ATMEL Corporation, at42qt1481 Datasheet - Page 34

• Manufacturer Part Number: at42qt1481
• Description: 48-key Qmatrix Ic
• Manufacturer: ATMEL Corporation

Error handling takes place whenever an error flag is detected, or the QT1481 stops
communicating (not shown). The error handling procedure is up to the designer. However
normally this would entail shutting down the product if the error is serious enough (for example,
a key that will not calibrate, or a FMEA \ EN60730 class error).
Normally it is not required to reload the setups, since the QT1481 itself stores a backup copy of
these in Flash memory should the EEPROM become corrupt. However the host should reset the
QT1481 so that the QT1481 copies the Flash setups to EEPROM, and then the QT1481 should
check that the EEPROM CRC code is correct.
Only if this fails should the EEPROM be reloaded by the host. One exception to this rule is just
after power-up, since a CRC error in the EEPROM setups at this point is clearly a critical error
that would require reloading. This happens at the factory, during the very first power-up cycle.
The “Last Com mand” command can be used at any time to resynchronize failed
communications, for example due to timing errors.
AT42QT1481
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