HD404818 Datasheet, PDF (19/100 Pages) Hitachi Semiconductor – 16-digit LCD driver

HD404818 Series
Reset
Setting the RESET pin high resets the MCU. At power-on or when cancelling the stop mode for the
oscillator, apply the reset input for at least t_RC for the oscillator to stabilize. In all other cases, at least two
instruction cycles of reset input are required for the MCU reset.
Table 1 shows the components initialized by MCU reset, and each of its status.
Table 1 Initial Values after MCU Reset
Items
Program counter (PC)
Initial Value
$0000
Status flag (ST)
1
Stack pointer (SP)
$3FF
V register (bank register) (V)
0
Interrupt
Interrupt enable flag (IE)
0
flags/mask
Interrupt request flag (IF)
0
Interrupt mask (IM)
1
I/O
Port data register (PDR)
All bits are 1
Data control register (DCR) All bits are 0
Port mode register A (PMRA) 0000
Port mode register B (PMRB) 0000
Timer/counters, Timer mode register A (TMA) 0000
serial interface
Timer mode register B (TMB) 0000
Timer mode register C (TMC) 0000
Serial mode register (SMR) 0000
Prescaler S
$000
Prescaler W
$00
Timer counter A (TCA)
$00
Timer counter B (TCB)
$00
Timer counter C (TCC)
$00
Timer load register B (TLR) $00
Timer load register C (TCR) $00
Octal counter
000
Contents
Execute program from the top of the ROM
address
Enable branching with conditional branch
instructions
Stack level is 0
Bank 0 (memory)
Inhibit all interrupts
No interrupt request
Masks interrupt request
Enable to transmit high
Output buffer is off (high impedance)
See Port Mode Register A section
See Port Mode Register B section
See Timer Mode Register A section
See Timer Mode Register B section
See Timer Mode Register C section
See Serial Mode Register section
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