MC908QY8CDWE Datasheet, PDF (199/232 Pages) Freescale Semiconductor, Inc – Addendum to MC68HC908QB8, rev. 3

POR RESET
Monitor Module (MON)
CONDITIONS
FROM Table 17-1
DEBUGGING
AND FLASH
PROGRAMMING
(IF FLASH
IS ENABLED)
NO
IRQ = V_TST?
YES
PTA0 = 1,
RESET VECTOR
BLANK?
YES
FORCED
MONITOR MODE
NO
NORMAL
USER MODE
HOST SENDS
8 SECURITY BYTES
PTA0 = 1,
NO
PTA1 = 1, AND
PTA4 = 0?
YES
NORMAL
MONITOR MODE
INVALID
USER MODE
IS RESET
POR?
NO
YES
YES
ARE ALL
SECURITY BYTES
NO
CORRECT?
ENABLE FLASH
DISABLE FLASH
MONITOR MODE ENTRY
EXECUTE
MONITOR CODE
YES
DOES RESET
NO
OCCUR?
Figure 17-9. Simplified Monitor Mode Entry Flowchart
MC68HC908QB8 Data Sheet, Rev. 3
Freescale Semiconductor
197