HT45R34 Holtek Semiconductor, HT45R34 Datasheet - Page 12

• Manufacturer Part Number: HT45R34
• Description: C/R to F Type 8-Bit OTP MCU
• Manufacturer: Holtek Semiconductor

www.DataSheet4U.com
To guarantee that the system oscillator is started and
stabilised, the SST or System Start-up Timer, provides
an extra-delay of 1024 system clock pulses when the
system is reset (power-up, WDT time-out or RES reset)
or when the system awakens from a Power Down state.
When a system reset occurs, the SST delay is added
during the reset period. Any wake-up the Power Down
mode will enable the SST delay.
An extra option load time delay is added during a system
reset (power-up, WDT time-out during normal mode or a
RES reset).
The functional unit device reset status are shown below.
The states of the registers is summarized in the table.
Rev. 1.20
Program Counter
Interrupt
Prescaler
WDT
Timer/Event Counter Off
Input/Output Ports
Stack Pointer
MP0
MP1
ACC
Program
Counter
TBLP
TBLH
WDTS
STATUS
INTC0
TMR
Register
Reset Timing Chart
(Power-on)
0000 0111
-000 0000
xxxx xxxx
xxxx xxxx
-xxx xxxx
-xxx xxxx
xxxx xxxx
--00 xxxx
--xx xxxx
Reset
000H
000H
Disable
Clear
Clear. After master reset,
WDT begins counting
Input mode
Points to the top of the stack
(Normal Operation)
WDT Time-out
uuuu uuuu
uuuu uuuu
0000 0111
-uuu uuuu
-uuu uuuu
-000 0000
--uu uuuu
--1u uuuu
xxxx xxxx
000H
12
(Normal Operation)
Note:
RES Reset
uuuu uuuu
uuuu uuuu
-uuu uuuu
-uuu uuuu
-000 0000
0000 0111
--uu uuuu
--uu uuuu
xxxx xxxx
000H
Most applications can use the Basic Reset Cir-
cuit as shown, however for applications with ex-
tensive noise, it is recommended to use the
Hi-noise Reset Circuit.
Reset Configuration
Reset Circuit
RES Reset
uuuu uuuu
uuuu uuuu
0000 0111
-uuu uuuu
-uuu uuuu
-000 0000
--uu uuuu
--01 uuuu
xxxx xxxx
(HALT)
000H
WDT Time-out
October 15, 2007
uuuu uuuu
uuuu uuuu
uuuu uuuu
-uuu uuuu
-uuu uuuu
uuuu uuuu
-uuu uuuu
--uu uuuu
--11 uuuu
HT45R34
(HALT)*
000H