em78p134n ELAN Microelectronics Corp, em78p134n Datasheet - Page 37

• 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)
5.6 Interrupt
The EM78P134N has five interrupts as listed below:
(1) TCC overflow interrupt
(2) Port 6 Input Status Change Interrupt
(3) External interrupt [(P60, /INT) pin]
(4) When TMR matches with PRD respectively in PWM
(5) When the comparators output changes
Before the Port 6 Input Status Changed Interrupt is enabled, reading Port 6 (e.g. "MOV
R6, R6") is necessary. Each pin of Port 6 will have this feature if its status changes.
Any pin configured as output or P60 pin configured as /INT, is excluded from this
function. The Port 6 Input Status Changed Interrupt can wake up the EM78P134N from
sleep mode if Port 6 is enabled prior to going into sleep mode by executing SLEP
instruction. When the device wakes-up, the controller will continue to execute the
program in-line if the global interrupt is disabled. If the global interrupt is enabled, it will
branch to the interrupt Vector 006H.
RF is the interrupt status register that records the interrupt requests in the relative
flags/bits. IOCF is an interrupt mask register. The global interrupt is enabled by the
ENI instruction and is disabled by the DISI instruction. When one of the interrupts
(enabled) occurs, the next instruction will be fetched from interrupt vector address.
Once in the interrupt service routine, the source of an interrupt can be determined by
polling the flag bits in RF. The interrupt flag bit must be cleared by instructions before
leaving the interrupt service routine, prior to enabling interrupts to avoid recursive
interrupts.
WDTE
Power-on
Voltage
Detector
Reset
/RESET
Oscillator
WDT
Figure 5-9 Controller Reset Block Diagram
WDT Timeout
VDD
8-Bit Microcontroller with OTP ROM
D
CLK
CLR
Q
Setup Time
RESET
EM78P134N
CLK
• 31