User Manual

35
T89C51AC2
Rev. B – 19-Dec-01
Figure 12. Col umn La tches Loadi ng P rocedu re
Note: The last page address used when loading the column latch is the one used to select the
page pr ogramming address.
9.3.6 P rogramming the F LASH
Spaces
User Th e fol lowi ng pro ced ure is use d to pro gram the U ser spa ce a nd is s umm ar ized in
Figure 13:
• Load up to one page of data in the column latches from address 0000h to 7FFFh .
• Disable the interru pts.
• Launc h the programming by writing the data sequence 50h followed by A0h in
FCON register (only from FM1 ).
The end of the programm ing indicated by the FBUSY flag cleared.
• En able the interrupts.
Extra Row The following proc edure is used to program the Extra Row space and is summarized in
Figure 13:
• Load data in the column latches from a ddres s FF80h to FFFFh.
• Disable the interru pts.
Column Latches
Loading
Data Load
DPTR= Address
ACC= Data
Exec:MOVX@DPTR,A
Last Byte
to load?
Column Latches Mapping
FCON = 08h (FPS=1)
Data memory Mapping
FCON = 00h (FPS = 0)
Save & Disable IT
EA= 0
Restore IT