Motorola MPC533 Reference Manual page 845

Writing EHV = 0 before HVS = 0 causes the current program
sequence to ABORT. The location for which the program
sequence was aborted may not have been programmed with
sufficient margins. The block containing that location must be
erased and reprogrammed before that block of the UC3F array
may be used reliably.
8. If more information needs to be programmed go to step 3.
9. Write SES = 0 in the UC3FCTL register.
Reset
Table 19-7. Program Interlock State Descriptions
State
S1 Normal Operation:
Normal array reads and register accesses. The
block protect information can be modified.
MOTOROLA
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
WARNING
T3
S2
T7
T1 T2
T6
S1
T5
T10
Figure 19-8. Program State Diagram
Mode
Chapter 19. CDR3 Flash (UC3F) EEPROM
S3
T4
S4
T8
T9
S5
Next
Transition Requirement
State
S2 T2 Write PE = 0, SES = 1.
UC3F Operation
19-23