Samsung S3F80JB User Manual

Page 288

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S3F80JB

EMBEDDED FLASH MEMORY INTERFACE

15-9

The Sector Erase Procedure in User Program Mode

1. Set Flash Memory User Programming Enable Register (FMUSR) to “10100101B”.

2. Set Flash Memory Sector Address Register (FMSECH and FMSECL).

3. Set Flash Memory Control Register (FMCON) to “10100001B”.

4. Set Flash Memory User Programming Enable Register (FMUSR) to “00000000B”.

SB1

Start

; Select Bank1

; User Programimg Mode Enable

; Set Sector Base Address

; User Prgramming Mode Disable

; Mode Select & Start Erase

FMCON #10100001B

; Select Bank0

FMUSR #00H

SB0

Finish One Sector Erase

FMSECH High Address of Sector
FMSECL Low Address of Sector

FMUSR #0A5H

Figure 15-8. Sector Erase Flowchart in User Program Mode

NOTES

1. If user erases a sector selected by Flash Memory Sector Address Register FMSECH and FMSECL,

FMUSR should be enabled just before starting sector erase operation. And to erase a sector, Flash

Operation Start Bit of FMCON register is written from operation stop ‘0’ to operation start ‘1’. That bit

will be cleared automatically just after the corresponding operation completed. In other words, when

S3F80JB is in the condition that flash memory user programming enable bits is enabled and executes

start operation of sector erase, it will get the result of erasing selected sector as user’s a purpose and

Flash Operation Start Bit of FMCON register is also clear automatically.

2. If user executes sector erase operation with FMUSR disabled, FMCON.0 bit, Flash Operation Start

Bit, remains 'high', which means start operation, and is not cleared even though next instruction is

executed. So user should be careful to set FMUSR when executing sector erase, for no effect on

other flash sectors.

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