GMS81508B HYNIX [Hynix Semiconductor], GMS81508B Datasheet - Page 37

• Manufacturer Part Number: GMS81508B
• Description: HYUNDAI MICRO ELECTRONICS 8-BIT SINGLE-CHIP MICROCONTROLLERS
• Manufacturer: HYNIX [Hynix Semiconductor]

GMS81508B/16B/24B
10. BASIC INTERVAL TIMER
The GMS815xxB has one 8-bit Basic Interval Timer that
is free-run and can not stop. Block diagram is shown in
Figure 10-1.
In addition, the Basic Interval Timer generates the time
base for watchdog timer counting. It also provides a Basic
interval timer interrupt (BITIF). As the count overflow
from FF
34
X
IN
H
PIN
to 00
H
, this overflow causes the interrupt to be
Select Input clock 3
Basic Interval Timer
clock control register
CKCTLR
[2:0]
000
001
010
011
100
101
110
111
[0D3
16
32
64
128
256
512
1024
2048
H
]
MUX
Figure 10-1 Block Diagram of Basic Interval Timer
BTS[2:0]
Table 10-1 Basic Interval Timer Interrupt Time
f
f
f
f
f
f
f
f
XIN
XIN
XIN
XIN
XIN
XIN
XIN
XIN
source
clock
CKCTLR
Source clock
16
32
64
128
256
512
1024
2048
[0F9
Internal bus line
8-bit up-counter
H
]
clear
BTCL
BITR
Read
generated. The Basic Interval Timer is controlled by the
clock control register (CKCTLR) shown in Figure 10-2.
Source clock can be selected by lower 3 bits of CKCTLR.
BITR and CKCTLR are located at same address, and ad-
dress 0F9
overflow
Interrupt (overflow) Period (ms)
H
@ f
is read as a BITR, and written to CKCTLR.
16.384
32.768
65.536
0.512
1.024
2.048
4.096
8.192
XIN
BITIF
To Watchdog timer (WDTCK)
= 8MHz
Basic Interval Timer Interrupt
HYUNDAI MicroElectronics
DEC. 1999 Ver 1.04