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M28W320CT, M28W320CB

Figure 11. Program Flowchart and Pseudo Code

a sequence.

2. If an error is found, the Status Register must be cleared (CLRS instruction) before further P/E.C. operations.

Write 40h or 10h

Command

AI03538

Start

Write Address

& Data

Read Status

Register

YES

NO

b7 = 1

YES

NO

b3 = 0

NO

b4 = 0

VPP Invalid

Error (1, 2)

Program

Error (1, 2)

Program instruction:

– write 40h or 10h command

– write Address & Data

(memory enters read status state after

the Program instruction)

do:

– read status register (E or G must be

toggled) if PES instruction given execute

suspend program loop

while b7 = 1

If b3 = 1, VPP invalid error:

– error handler

If b4 = 1, Program error:

– error handler

YES

End

YES

NO

b1 = 0

Program to Protected

Block Error (1, 2)

If b1 = 1, Program to protected block error:

– error handler

Suspend

Suspend

Loop

NO

YES