
HT49C10
26
September 28, 1999
Mask option
The following shows 16 kinds of mask options in the HT49C10. All these options should be defined in
order to ensure proper system functioning.
No.
Mask Option
1
OSC type selection. This option is to decide if an RC or crystal oscillator is selected as sys-
tem clock.
2
Clock source selection of WDT, RTC and Time Base. There are three types of selection: sys-
tem clock/4 or RTC OSC or WDT OSC.
3
WDT enable/disable selection. WDT can be enabled or disabled by mask option.
4
CLR WDT times selection. This option defines how to clear the WDT by instruction. One
time means that the CLR WDT can clear the WDT. Two times means only if both of the
CLR WDT1 and CLR WDT2 have been executed, the WDT can be cleared.
Time Base time-out period selection. The Time Base time-out period ranges from fs/2
12
to
fs/2
. fs means the clock source selected by mask option.
5
6
Buzzer output frequency selection. There are eight types frequency signals for buzzer out-
put: fs/2
~fs/2
. fs means the clock source selected by mask option.
7
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 chip from a HALT by a falling edge.
8
Pull-high selection. This option is to decide whether the pull-high resistance is viable or not
on the PA0~PA3.
9
PA CMOS or NMOS selection.
PA0~PA3 can be selected as CMOS or NMOS structure, but PA4~PA7 are always NMOS.
When the CMOS is selected, the related pins can only be used for output operations. When
the NMOS is selected, the related pins can be used for input or output operations.
10
Clock source selection of timer/event counter. There are two types of selection: system clock
or system clock/4.
11
I/O pins share with other functions selection.
PA0/BZ, PA1/BZ: PA0 and PA1 can be set as I/O pins or buzzer outputs.
PA3/PFD: PA3 can be set as I/O pins or PFD output.
12
LCD common selection. There are three types of selection: 2 commons (1/2 duty) or 3 com-
mons (1/3 duty) or 4 commons (1/4 duty). If the 4 commons are selected, the segment output
pin SEG18 will be set as a common output.
13
LCD bias power supply selection.
There are two types of selection: 1/2 bias or 1/3 bias.
14
LCD bias type selection.
This option is to decide what kind of bias is selected, R type or C type.
15
LCD driver clock selection. There are seven types frequency signals for LCD driver circuits:
fs/2
~fs/2
. fs means the clock source selected by mask option.