HT49CV5 Holtek Semiconductor, HT49CV5 Datasheet - Page 30

• Manufacturer Part Number: HT49CV5
• Description: A/D
• Manufacturer: Holtek Semiconductor

Note:
Options
The following shows the configuration options in the HT49RV5/HT49CV5. All these options should be defined in order
to ensure a properly functioning system.
Rev. 1.20
OSC type selection. This option is to decide if an RC or crystal or 32768Hz crystal oscillator is chosen as the system
clock.
f
f
WDT enable/disable selection. WDT can be enabled or disabled by option.
WDT time-out period selection. There are four types of selection: WDT clock source divided by f
f
CLR WDT times selection. This option defines the method to clear the WDT by instruction. One time means that
the CLR WDT instructions can clear the WDT. Two times means only if both of the CLR WDT1 and CLR
WDT2 instructions have been executed, the WDT can be cleared.
Buzzer output frequency selection. There are eight types of frequency signals for buzzer output: f
Wake-up selection. This option defines the wake-up capability. External I/O pins (PA only) all have the capability to
wake-up the chip from a HALT by a falling edge. (bit option)
Pull-high selection.
This option is to determine whether the pull-high resistance is viable or not in the input mode of the I/O ports. PA,
PB0~PB3, PC6~PC7, PD0~PD1 and PD4~PD7 can be independently selected. (bit option)
RMT Pull-high selection. This option is to determine whether a pull-high resistance is viable or not in the input pin.
I/O pins shared with other function selections. PA0/BZ, PA1/BZ, PA3/PFD: PA0, PA1 and PA3 can be set as I/O pins
or buzzer outputs.
VFD driver clock selection. There are 8 types of frequency signals for the VFD driver circuits: f
VFD ON/OFF at HALT selection, VFD ON at HALT works only when the VFD clock source selects RTC OSC
WDT
S
WDT
f
f
S
S
: VFD, RTC and Buzzer clock source selection. There are two types of selections: system clock/4 or RTC OSC
means the clock source selected by options.
stands for the clock source selection by options.
: WDT clock source selection. There are three types of selections: system clock/4 or RTC OSC or WDT OSC
/2
13
*1: To make sure that the system oscillator has stabilized, the SST provides an extra delay of 1024 system
*2: Since the low voltage has to maintain its original state for longer than 1ms, therefore a 1ms delay enters the
~f
clock pulses before starting normal operation.
reset mode.
WDT
/2
14
, f
WDT
/2
14
~f
WDT
/2
15
or f
WDT
/2
15
Low Voltage Reset
~f
WDT
Options
/2
30
16
HT49RV5/HT49CV5
S
/2
WDT
0
S
~f
/2~f
/2
S
April 14, 2006
/2
12
S
7
/2
~f
.
8
WDT
,
/2
13
,