King Billion Electronics Co., Ltd.
HE89C21
駿 億 電 子 股 份 有 限 公 司
HE80000 SERIES
The contents of T1H and
T1L almost loaded into
Timer1 immediately
when Timer1 is turned on
after reset.
T1H
T1L
Auto reload when
Timer1 underflow
"Timer1 Counter"
decreases 1
No
Count TO
0xFFFFh
Yes
Start Timer1
Interrupt Request.
T1_INT
The Timer1 related control registers are list as below:
Register Address
Field
Bit position Mode
Description
IER
0x02
TC1_IER
2
R/W 0: TC1 interrupt is disabled. (default)
1: TC1 interrupt is enabled.
T1L
T1H
OP1
0x03
0x04
0x09
T1L[7:0]
T1H[7:0]
TC1E
7~0
7~0
2
W
W
Low byte of TC1 pre-load value
High byte of TC1 pre-load value
R/W 0: TC1 is disabled. (default)
1: TC1 is enabled.
11. Timer2
Timer2 is similar in structure to Timer1 except that clock source of Timer2 comes from the system clock
“Fsys”/1.5. The system clock “Fsys” varies depending on the operation modes of the MCU.
The Timer2 consists of two 8-bit write-only preload registers T2H and T2L and 16-bit down counter. If
Timer2 is enabled, counter will decrement by one with each incoming clock pulse. Timer2 interrupt will
be generated when the counter underflows - counts down to FFFFH. And it will be automatically reloaded
January 20, 2003
10
V1.0E
KB [ King blillion Electronics Co.,Ltd. ]
