em78p134n ELAN Microelectronics Corp, em78p134n Datasheet - Page 29

• Manufacturer Part Number: em78p134n
• Description: 8-bit Microcontroller With Otp Rom
• Manufacturer: ELAN Microelectronics Corp

Product Specification (V1.6) 06.02.2010
(This specification is subject to change without further notice)
Only one of Cases 2 and 3 can be enabled before entering sleep mode. That is,
[a] if Port 6 input status changed interrupt is enabled before SLEP, WDT must be
If Port 6 Input Status Changed Interrupt is used to wake-up the EM78P134N (Case [a]
above), the following instructions must be executed before SLEP:
MOV
CONTW
WDTC
MOV
IOW
MOV
MOV
IOW
ENI (or DISI)
SLEP
[b] if WDT is enabled before SLEP, Port 6 Input Status Change Interrupt must be
1. After waking up from sleep mode, the WDT is automatically enabled. The WDT
2. To avoid a reset from occurring when the Port 6 Input Status Changed Interrupt
disabled by software. However, the WDT bit in the option register remains
enabled. Hence, the EM78P134N can be awakened only by Case 1 or 3.
disabled. Hence, the EM78P134N can be awakened only by Case 1 or 2. Refer to
the section on Interrupt.
enable/disable operation after waking up from sleep mode should be properly
defined in the software.
enters into an interrupt vector or is used to wake-up the MCU, the WDT prescaler
must be set above the 1:1 ratio.
A, @xxxx1110b
A, @0xxxxxxxb
RE
R6, R6
A, @00000x1xb
RF
NOTE
; Select WDT prescaler,
; the prescaler
; 1:1
; Enable Port 6 input change
; interrupt
; Enable (or disable) global
; interrupt
; Clear WDT and prescaler
; Disable WDT
; Read Port 6
; Sleep
8-Bit Microcontroller with OTP ROM
must be set over
EM78P134N
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