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For your awareness, it is important to highlight that the AM29PDL128Gxx family series is obsolete and not recommended for new designs.
The user does have direct access the main physical memory cells. Each WORD (16-bit) location can be programmed individually, but each WORD (16-bit) location cannot be erased individually. The smallest erase resolution is the Sector Erase embedded operation.
Caution should be used with programming the SecSi (sector) region, as it can only be programmed once and cannot be erased.
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