Winbond W29C020/040 Operation Notes

This chip has two boot blocks with lockout feature. This feature can be
enabled by setting the bit0(the first boot block) or the bit7(the last boot block) in the
programmer's Protect-Setting-Byte(PSB). The other bits(bit1..6) are don't-care.

Before writing, all the slaves will be un-locked and erased. After the
contents of master IC has been copied into the slaves, the boot block will
be locked according to its bit status in the PSB byte.(1 for lock, 0 for no-lock)

The VERIFY command will compare the content of all salves with the master device first, and then compare their lock status with the PSB setting. Only those which has both comparison passed will be recognized as a good one.

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