ZHCS290G September 2009 – June 2018 TCA8418
PRODUCTION DATA.
In the Interrupt Status Register (see Table 10), bit 4 is used to indicate the detection of a CTRL-ALT-DEL key sequence. Certain key press sequences trigger this bit to register a CAD_INT improperly.
| BIT | NAME | DESCRIPTION |
|---|---|---|
| 7 | N/A | Always 0 |
| 6 | N/A | Always 0 |
| 5 | N/A | Always 0 |
| 4 | CAD_INT | CTRL-ALT-DEL key sequence status. Requires writing a 1 to clear interrupts. |
| 0 = interrupt not detected | ||
| 1 = interrupt detected | ||
| 3 | OVR_FLOW_INT | Overflow interrupt status. Requires writing a 1 to clear interrupts. |
| 0 = interrupt not detected | ||
| 1 = interrupt detected | ||
| 2 | K_LCK_INT | Keypad lock interrupt status. This is the interrupt to the processor when the keypad lock sequence is started. Requires writing a 1 to clear interrupts. |
| 0 = interrupt not detected | ||
| 1 = interrupt detected | ||
| 1 | GPI_INT | GPI interrupt status. Requires writing a 1 to clear interrupts. |
| 0 = interrupt not detected | ||
| 1 = interrupt detected | ||
| Can be used to mask interrupts | ||
| 0 | K_INT | Key events interrupt status. Requires writing a 1 to clear interrupts. |
| 0 = interrupt not detected | ||
| 1 = interrupt detected |
The following key press combinations will cause a false CAD_INT: