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CHAPTER 21 RESET FUNCTION
User’s Manual U19780EJ2V0UD
557
Table 21-2. Hardware Statuses After Reset Acknowledgment (1/4)
Hardware After
Reset
Acknowledgment
Note 1
Program counter (PC)
The contents of the
reset vector table
(0000H, 0001H) are set.
Stack pointer (SP)
Undefined
Program status word (PSW)
02H
Data memory
Undefined
Note 2
RAM
General-purpose registers
Undefined
Note 2
Port registers (P0 to P4, P6 to P8, P12) (output latches)
00H
Port mode registers (PM0 to PM4, PM6 to PM8, PM12)
FFH
Pull-up resistor option registers (PU0, PU1, PU3, PU4, PU7, PU12)
00H
Internal memory size switching register (IMS)
CFH
Note 3
Notes 1.
During reset signal generation or oscillation stabilization time wait, only the PC contents among the
hardware statuses become undefined. All other hardware statuses remain unchanged after reset.
2.
When a reset is executed in the standby mode, the pre-reset status is held even after reset.
3.
The initial values of the internal memory size switching register (IMS) after a reset release is constant
(IMS = CFH) in all products of the 78K0/Kx2-A microcontrollers, regardless of the internal memory
capacity. Therefore, set the value corresponding to each product as indicated in Table 3-1.
Remark
The special function register (SFR) mounted depend on the product. See
3.2.3 Special function
registers (SFRs)
.