| Items Variety | Detent | Attached switches travel |
| Single-shaft, Single-unit | Without | Center | 41 | 0.5, 1.5mm |
| | | | |
Since the security bit address overlaps the address of the security byte of the signature mode, it can be used to check indirectly whether the security bit has been programmed or not. Therefore, the security bit verification is a mere read operation of the security byte of the signature row (OFFH = security bit pro- grammed; OOH = security bit unprogrammed). Note that during the security bit programming, the reading of the security byte does not necessarily indicate that the security bit has been successfully pro- grammed. Thus, it is recommended that two consec- utive known bytes in the EPROM array be read and the wrong data should be read at least once, be- cause it is highly improbable that random data coin- cides with the correct ones twice.
