HMS87C5216 ETC1 [List of Unclassifed Manufacturers], HMS87C5216 Datasheet - Page 70

• Manufacturer Part Number: HMS87C5216
• Description: CMOS SINGLE-CHIP 8-BIT MICROCONTROLLER FOR UR(Universal Remocon) & WIRELESS KEYBOARD
• Manufacturer: ETC1 [List of Unclassifed Manufacturers]

HMS87C5216
18. CLOCK GENERATOR
Clock generating circuit consists of Clock Pulse Generator
(C.P.G), Prescaler, Basic Interval Timer (B.I.T) and Watch Dog
Prescaler consists of 12-bit binary counter. The clock supplied
from oscillation circuit is input to prescaler (fex). The divided
Figure 18-1 Block Diagram of Clock Generator
Figure 18-2 Block diagram of Prescaler
ENPCK
fcpu
fex
Peripheral
CKCTLR
PRESCALER
Circuit
8
OSC
PS0
ENPCK
0
PS1
3
1
PS1
PS1
MUX
2
fex
PS2
3
PS2
4
PS3
5
PS3
C.P.G
BTCL
0
PS4
Internal Data Bus
PS4
B.I.T (8)
PS5
fcpu
PS5
PS6
7
PS6
Timer. The clock applied to the Xin pin divided by two is used as
the internal system clock.
output from each bit of prescaler is provided to peripheral hard-
ware.
PS7
PS7
WDTON
0
0
COMPARATOR
PS8
PS8
WDT (6)
WDTR
9
6
Internal System Clock
PS9
PS9
PS10 PS11 PS12
5
5
PS10 PS11
WDTCL
6
6
IFBIT
To Reset
Circuit
SEP. 2004 Ver 1.01
IFWDT
PS12
Peripheral
B.I.T