SST89E554 SST [Silicon Storage Technology, Inc], SST89E554 Datasheet - Page 34

• Manufacturer Part Number: SST89E554
• Description: FlashFlex51 MCU
• Manufacturer: SST [Silicon Storage Technology, Inc]

The Sector-Erase command erases all of the bytes in a
sector. The sector size for the flash memory Blocks is 128
Bytes. The selection of the sector to be erased is deter-
mined by the contents of SFAH and SFAL.
The Byte-Program command programs data into a single
byte. The address is determined by the contents of SFAH
and SFAL. The data byte is in SFDT.
The Byte-Verify command allows the user to verify that the
device has correctly performed an Erase or Program com-
mand.
Byte-Verify command returns the data byte in SFDT if the
command is successful. The user is required to check that
the previous flash operation has fully completed before
issuing a Byte-Verify. Byte-Verify command execution time
is short enough that there is no need to poll for command
completion and no interrupt is generated.
Prog-SB3, Prog-SB2, Prog-SB1 commands are used to
program the Security bits (see Table 8-1). Completion of
any of these commands, the security options will be
updated immediately.
Security bits previously in un-programmed state can be
programmed by these commands. Prog-SB3, Prog-SB2
and Prog-SB1 commands should only reside in Block 1.
Prog-SC0 command is used to program the SC0 bit. This
command only changes the SC0 bit and has no effect on
BSEL bit until after a reset cycle.
SC0 bit previously in un-programmed state can be pro-
grammed by this command. The Prog-SC0 command
should reside only in Block 1.
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©2001 Silicon Storage Technology, Inc.
SST89E564 / SST89V564 / SST89E554 / SST89V554
34
Prog-SC1 command is used to program the SC1 bit. This
command only changes the SC1 bit and has no effect on
BSEL bit until after a reset cycle.
SC1 bit previously in un-programmed state can be pro-
grammed by this command. The Prog-SC1 command
should reside only in Block 1.
There are no IAP counterparts for the External Host com-
mands Select-Block0 and Select-Block1.
4.2.5 Polling
A command that uses the polling method to detect flash
operation completion should poll on the FLASH_BUSY bit
(SFST[2]). When FLASH_BUSY de-asserts (logic 0), the
device is ready for the next operation.
MOVC instruction may also be used for verification of the
Programming and Erase operation of the flash memory.
MOVC instruction will fail if it is directed at a flash block that
is still busy.
4.2.6 Interrupt Termination
If interrupt termination is selected, (SFCM[7] is set), then
an interrupt (INT1) will be generated to indicate flash opera-
tion completion. Under this condition, the INT1 becomes an
internal interrupt source. The INT1# pin can now be used
as a general purpose port pin and it cannot be the source
of External Interrupt 1 during In-Application Programming.
In order to use an interrupt to signal flash operation termi-
nation. EX1 and EA bits of IE register must be set. The IT1
bit of TCON register must also be set for edge trigger
detection.
Preliminary Specifications
FlashFlex51 MCU
S71181-03-000 9/01
384