EM78156EAS EMC [ELAN Microelectronics Corp], EM78156EAS Datasheet - Page 19

• Manufacturer Part Number: EM78156EAS
• Description: 8-Bit Microcontroller with MASK ROM
• Manufacturer: EMC [ELAN Microelectronics Corp]

Product Specification (V1.3) 07.29.2004
(This specification is subject to change without further notice)
2
(I) Wake-up from Port 6 Input Status change
NOTE: Software disables WDT (watchdog timer) but hardware must be enabled before applying Port
PORT
Weakly
Pull-up
(a) Before SLEEP
(b) After Wake-up
4.5 RESET and Wake-up
1. Disable
2. Read I/O Port 6 (MOV R6,R6)
3. Execute "ENI" or "DISI"
4. Enable interrupt (Set IOCF.1)
5. Execute "SLEP" instruction
1. IF "ENI" → Interrupt vector (008H)
2. IF "DISI" → Next instruction
6 Changed Wake-up function. (CODE Option Register and Bit 11 (ENWDT) are set to “1”).
VCC
Rex*
Table 4 Usage of Port 6 Input Change Wake-up/Interrupt Function
4.5.1 RESET
A RESET is initiated by one of the following events-
(1) Power on reset.
WDT2
(using very carefully)
Usage of Port 6 input status changed Wake-up/Interrupt
ROC
Fig. 8 The Circuit of I/O Port with R-option(P50,P51)
*The Rex is 430K ohm external resistor
0
1
M
U
X
Q
Q
Q
Q
(II) Port 6 Input Status Change Interrupt
P
R
C
L
P
R
C
L
PCRD
CLK
D
D
2. Execute "ENI"
3. Enable interrupt (Set IOCF.1)
4. IF Port 6 change (interrupt)
→ Interrupt vector (008H)
1. Read I/O Port 6 (MOV R6,R6)
8-Bit Microcontroller with MASK ROM
PDRD
PCWR
PDWR
EM78156E
IOD
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