MSP430x11x1

 

 

MIXED SIGNAL MICROCONTROLLER

 

 

SLAS241C ± SEPTEMBER 1999 ± REVISED JUNE 2000

 

 

 

flash memory control register FCTL3 (continued)

BUSY

012Ch, bit0,

The BUSY bit shows if an access to the flash memory is allowed (BUSY=0), or

 

 

if an access violation occurs. The BUSY bit is read-only, but a write operation is

 

 

allowed. The BUSY bit should be tested before each write and erase cycle. The

 

 

flash timing-generator hardware immediately sets the BUSY bit after start of a

 

 

write, segment-write, erase, or mass erase operation. If the timing generator has

 

 

completed the operation, the BUSY bit is reset by the hardware.

 

 

No program code can be executed from the busy flash memory during the entire

 

 

program or erase cycle.

 

 

0: Flash memory is not busy.

 

 

1: Flash memory is busy, and remains in busy state if segment write function

 

 

is in wait mode.

KEYV,

012Ch, bit1

Key violation

 

 

0: Key 0A5h (high byte) was not violated.

 

 

1: Key 0A5h (high byte) was violated. Violation occurs when a write access to

 

 

registers FCTL1, FCTL2, or FCTL3 is executed and the high byte is not

 

 

equal to 0A5h. If the security key is violated, bit KEYV is set and a PUC is

 

 

performed.

ACCVIFG,

012Ch, bit2

Access violation interrupt flag

 

 

The access-violation flag is set when any combination of control bits other than

 

 

those shown in Table 3 is attempted, or an instruction is fetched while a

 

 

segment-write operation is active.

 

 

Reading the control registers will not set the ACCVIFG bit.

 

 

NOTE: The respective interrupt-enable bit ACCVIE is located in the interrupt

 

 

enable register IE1 in the special function register. The software can set

 

 

the ACCVIFG bit. If set by software, an NMI is also executed.

WAIT,

012CH, bit3

In the segment-write mode, the WAIT bit indicates that data has been written and

 

 

the flash memory is prepared to receive the next data for programming. The

 

 

WAIT bit is read only, but a write to the WAIT bit is allowed.

0: The segment-write operation has began and programming is in progress.

1: The segment-write operation is active and data programming is complete.

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Texas Instruments MSP430x11x1 warranty Busy, Keyv, Accvifg, Wait