HT46RU25 Holtek Semiconductor Inc., HT46RU25 Datasheet - Page 42

• Manufacturer Part Number: HT46RU25
• Description: Ht46ru25/ht46cu25 -- A/d Type 8-bit Mcu
• Manufacturer: Holtek Semiconductor Inc.

Options
The following shows the kinds of options in the device. ALL the options must be defined to ensure a proper functioning
system.
Rev. 1.30
OSC type selection.
This option is to determine whether an RC or crystal or 32768Hz crystal oscillator is chosen as a system clock.
If 32768Hz crystal oscillator is chosen as system clock or as f
WDT, RTC and Time Base clock source selection.
There are three types of selections: system clock/4 or RTC OSC or WDT OSC.
WDT enable/disable selection.
WDT can be enabled or disabled by option.
CLRWDT times selection.
This option defines how to clear the WDT by instruction. One time means that the CLR WDT instruction can clear
the WDT. Two times means only if both of the CLR WDT1 and CLR WDT2 instructions have been executed,
then WDT can be cleared.
Time Base time-out period selection.
The Time Base time-out period ranges from 2
Wake-up selection.
This option defines the wake-up function activity. External I/O pins (PA only) all have the capability to wake-up the
device from a HALT by a falling edge. (Bit option)
Pull-high selection.
This option is to determine whether a pull-high resistance is visible or not in the input mode of the I/O ports. PA and
PB are bit option; PC, PD, PF and PG are port option.
PFD selection.
PA3: level output or PFD0 (Timer0) output or PFD1 (Timer1)
PWM selection: (7+1) or (6+2) mode
PD0: level output or PWM0 output
PD1: level output or PWM1 output
PD2: level output or PWM2 output
PD3: level output or PWM3 output
WDT time-out period selection.
2
I
LVR selection.
LVR has enable or disable options
2
12
C Bus function: enable or disable
/f
S
~2
13
/f
S
, 2
13
/f
S
~2
14
/f
S
, 2
14
/f
S
~2
15
/f
S
, 2
15
/f
S
~2
12
16
/f
S
/f
S
to 2
.
Options
15
42
/f
S
. f
S
S
means the clock source selected by options.
, the PC6 and PC7 will be used as oscillator pins.
HT46RU25/HT46CU25
March 9, 2007