Texas Instruments MSP430x1xx - Manual (Page 437)

Flash Memory Access via JTAG and Software
C-25
Flash Memory
C.5.3.3 Example, Programming Byte Sequences Into a Flash Memory Module via Software
Sequences of data, bytes, or words can use the segment-write feature. This
reduces the programming time by about one half.
yes
no
no
yes
Set Pointer for Start and End
Clear Lock Bit
SEG WRT = WRT =0
End of Segment Write
no
yes
Fxkey .set 03300h
Fwkey .set 0A500h
Frkey .set 09600h
Test_Busy1
BIT
JNZ
#BUSY,&FCTL3 ; Flash busy? SEGWRT ended?
Test_Busy1
MOV #(Fwkey+WRT+SEGWRT),&FCTL1 ; Segment write
Test_WAIT1
RAM2FLASH
MOV #Start_Ptr,Rx
MOV #End_Ptr,Ry
MOV #Fkey,&FCTL3
CMP Rx,Ry ; All data programmed?
JZ End_Seg_Write
MOV.B @Rx+,(Flash_Start_Ptr–Start_ptr–1) (Rx)
; Program data: in this example one byte
BIT #03Fh,Rx
JNZ Test_Wait1
; Segment border?
Test_Wait2
BIT #WAIT,&FCTL3 ; Test if data written
JZ Test_Wait2
MOV #Fwkey,&FCTL1 ; Stop segment write
JMP Test_busy1 ; Segment write ends if busy=0
End_Seg_Write
; All data are programmed
MOV #Fwkey,&FCTL1 ; Stop segment write
Test_Busy2
BIT #BUSY,&FCTL3 ; Segment write ended?
JNZ Test_Busy2
XOR #(Fxkey+Lock),&FCTL3 ; Change Lock bit to ’1
; Ensure that neither Watchdog Timer, nor
; interrupts nor Low–Power Modes may corrupt
; proper execution
yes
no
Busy ?
SEG WRT = WRT =1
BIT
JNE
#WAIT,&FCTL3
Test_WAIT1
; Clear lock bit
WAIT = 1
Write Byte to Flash
Segment
border?
yes
no
WAIT = 1
Busy ?
yes
no
SEG WRT = WRT =0
All data
Programmed?