DM-COP8/28D National Semiconductor, DM-COP8/28D Datasheet - Page 33

• Manufacturer Part Number: DM-COP8/28D
• Description: CABLE FOR DEBUG MODULE 28-DIP
• Manufacturer: National Semiconductor

Specifications of DM-COP8/28D

• Accessory Type: 28-DIP Target Cable
• For Use With/related Products: MetaLink Debug Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *DM-COP8/28D

of data from the stack and decrements or increments the stack pointer.
Interrupt Routines
There are two methods to get the interrupt routines:
1. Without a Vector Table
2. With a Vector Table
Polling—All interrupts cause an immediate jump to a single location in mem-
ory. The user program must poll all interrupt pending bits to determine the
cause of the interrupt. Once the cause is determined, the user program may
jump to an appropriate interrupt handling routine.
Preset Location—Each interrupt causes the microcontroller to jump to a dif-
ferent place in memory. The location is specified by the microcontroller de-
signer. The user program must store the interrupt handling routine at the
specified location.
A vector table is a list of start addresses for each of the program's interrupt
routines. This table is used by the microcontroller to determine where to jump
when a particular interrupt occurs.
Direct Jump—The microcontroller may automatically read the vector table
when an interrupt occurs and jump directly to the specified address.
VIS Instruction—The microcontroller may jump to a single location in mem-
ory for all interrupts. The user program may call a special instruction (VIS)
to cause the microcontroller to jump to the specified address.
MICROCONTROLLER BASICS
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