
131
CHAPTER 7 RESETS
7.4
Reset Operation
When a reset is cleared, the memory locations from which the mode data and the reset
vectors are read are selected according to the setting of the mode pins, and a mode
fetch is performed. Mode setting data determines the CPU operating mode and the
execution start address after a reset operation ends. For power-on or recovery from
stop mode by a reset, a mode fetch is performed when the oscillation stabilization wait
time elapses.
■
Overview of Reset Operation
Figure 7.4-1 shows the reset operation flow.
Figure 7.4-1 Reset Operation Flow
■
Mode Pins
Setting the mode pins (MD0 to MD2) specifies how to fetch the reset vector and the mode data. Fetching
the reset vector and the mode data is performed in the reset sequence. See Section "9.2 Mode Pins of
Memory Access Mode", for details on mode pins.
During a reset
Po
w
er-on reset
Stop mode
External reset
Soft
w
are reset
Watchdog timer reset
Oscillation stabilization
w
ait
and reset state
Fetching the mode data
Fetching the reset vector
CPU executes an instruction,
fetching instruction codes from
the address indicated by the
reset vector.
Pin state and function
change associated
w
ith
external bus mode
Mode fetch
(Reset operation)
Normal operation
(Run state)
Summary of Contents for MB90390 Series
Page 2: ......
Page 4: ......
Page 17: ...xiii APPENDIX D List of Interrupt Vectors 690 INDEX 695 ...
Page 18: ...xiv ...
Page 132: ...104 CHAPTER 5 CLOCKS ...
Page 152: ...124 CHAPTER 6 CLOCK MODULATOR ...
Page 210: ...182 CHAPTER 11 TIME BASE TIMER ...
Page 218: ...190 CHAPTER 12 WATCHDOG TIMER ...
Page 264: ...236 CHAPTER 14 16 BIT RELOAD TIMER WITH EVENT COUNT FUNCTION ...
Page 274: ...246 CHAPTER 15 WATCH TIMER ...
Page 306: ...278 CHAPTER 17 DTP EXTERNAL INTERRUPTS ...
Page 338: ...310 CHAPTER 18 8 10 BIT A D CONVERTER ...
Page 364: ...336 CHAPTER 19 UART0 UART1 ...
Page 398: ...370 CHAPTER 20 UART2 UART3 Figure 20 5 2 ORE Set Timing Receive data RDRF ORE ...
Page 432: ...404 CHAPTER 20 UART2 UART3 ...
Page 482: ...454 CHAPTER 22 SERIAL I O ...
Page 560: ...532 CHAPTER 24 STEPPING MOTOR CONTROLLER ...
Page 582: ...554 CHAPTER 27 ROM MIRRORING MODULE ...
Page 632: ...604 CHAPTER 29 EXAMPLES OF SERIAL PROGRAMMING CONNECTION ...
Page 722: ...694 APPENDIX ...
Page 723: ...695 INDEX The index follows on the next page This is listed in alphabetic order ...
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