AT89C5131A-RDTIM Atmel, AT89C5131A-RDTIM Datasheet - Page 30

• Manufacturer Part Number: AT89C5131A-RDTIM
• Description: C5131A 32K FLASH USB VQFP64 IND, 5V
• Manufacturer: Atmel

Status of the Flash Memory
Selecting FM0/FM1
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AT89C5131
The Flash memory enters a busy state as soon as programming is launched. In this
state, the memory is not available for fetching code. Thus to avoid any erratic execution
during programming, the CPU enters Idle mode. Exit is automatically performed at the
end of programming.
Note:
The bit FBUSY in FCON register is used to indicate the status of programming.
FBUSY is set when programming is in progress.
The bit ENBOOT in AUXR1 register is used to choose between FM0 and FM1 mapped
up to F800h.
Interrupts that may occur during programming time must be disabled to avoid any spuri-
ous exit of the idle mode.
4136C–USB–04/05