W78ERD2_07 Datasheet, PDF (58/76 Pages) Winbond – 8-BIT MICROCONTROLLER

W78ERD2/W78ERD2A
17. OPTION BITS REGISTER
In the on-chip Flash EPROM writer programming mode mode, the flash EPROM can be programmed
and verified repeatedly. Until the code is ready, it can be protected by properly setting option bits.
Option bits control the initial configuration of W78ERD2, including code protection, system clock mode
selection (6T/12T), H/W reboot mode selection and oscillator control.
Lock bit
This bit is used to protect the code in the W78ERD2. It may be set after the programmer finishes
programming and verifies the sequence. Once this bit is set to logic-0, both the Flash EPROM data
and Option Bits Register cannot be accessed again.
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