EM78159NAS EMC [ELAN Microelectronics Corp], EM78159NAS Datasheet - Page 23

• Manufacturer Part Number: EM78159NAS
• Description: 8-Bit Microcontroller with OTP ROM
• Manufacturer: EMC [ELAN Microelectronics Corp]

2
Product Specification (V1.0) 03.10.2006
(This specification is subject to change without further notice)
PORT
Vdd = 3V, set up time period = 18ms ± 30%
Vdd = 5V, set up time period = 16.8ms ± 30%
Weakly
Pull-up
4.5 RESET and Wake-up
VCC
Rex*
4.5.1 RESET
A RESET is initiated by one of the following events-
1) Power on reset.
2) /RESET pin input "low," or
3) WDT time-out (if enabled).
The device is kept under RESET condition for a period of approximately 18ms
oscillator start-up timer period) after a reset is detected. And if the /Reset pin goes
“low” or WDT time-out is active, a reset is generated. Once a RESET occurs, the
following functions are performed:
The oscillator is running, or will be started.
The Program Counter (R2) is set to all "0."
All I/O port pins are configured as input mode (high-impedance state).
ROC
*The Rex is 430K ohm external resistor
Figure 4-5 I/O Port with R-option (P50,P51) Circuit
0
1
M
U
X
Q
Q
Q
Q
P
R
C
L
P
R
C
L
PCRD
CLK
D
D
PDRD
PCWR
PDWR
8-Bit Microcontroller with OTP ROM
EM78P159N
2
IOD
(one
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