EM78P153EN EMC [ELAN Microelectronics Corp], EM78P153EN Datasheet - Page 23

• Manufacturer Part Number: EM78P153EN
• Description: EM78P153E is an 8-bit microprocessor with low-power and high-speed CMOS technology
• Manufacturer: EMC [ELAN Microelectronics Corp]

This specification is subject to change without prior notice.
4.7 Oscillator
/IRQn
1. Oscillator Modes
Table 6 Oscillator Modes Defined by OSC1 and OSC2
IRC(Internal RC oscillator mode)
ERC(External RC oscillator mode)
HXT(High XTAL oscillator mode)
LXT(Low XTAL oscillator mode)
The EM78P153E can be operated in four different oscillator modes, such as Internal RC oscillator
mode (IRC), External RC oscillator mode (ERC), High XTAL oscillator mode(HXT), and Low XTAL
oscillator mode(LXT). User can select one of them by programming OCS1 and OSC2 in the CODE
Option register. Table 6 depicts how these four modes are defined.
The up-limited operation frequency of crystal/resonator on the different VDDs is listed in Table 7.
<Note> The transient point of system frequency between HXT and LXY is around 400 KHz.
VCC
/RESET
D
RF
CLK
P
R
C
L
Mode
Q
Q
_
Fig. 11 Interrupt Input Circuit
IOCF
Q
Q
_
IOCFRD
RFWR
P
R
C
L
CLK
23
OSC1
D
RFRD
1
1
0
0
IOCFWR
IRQn
IRQm
OSC2
1
0
1
0
EM78P153E
IOD
ENI/DISI
OTP ROM
2002/03/01
INT