SLAS191A datasheet(63/86 Pages) TI

63 / 86 page

4–1

4 Treatment of Interrupts

This chapter describes the special treatment of interrupts in the Monitor environment.

4.1

Use of Interrupts in the Monitor Environment

The interrupt structure of the MSP430 is fully supported by the terminal program with one exception, the NMI

interrupt has the same interrupt vector as the RESET interrupt.

There are no restrictions on the interrupt flags, but certain restrictions apply to the interrupt vectors. It is

impossible to program the interrupt vectors located in the address range FFECh to FFFEh, because they

are preprogrammed in the EPROM area and can not be modified. The Monitor Program has the flexibility

to allow a second set of interrupt vectors in the RAM address range 3E0h to 3FEh (5E0h–5FEh for the

MSP430X33x family) as shown in Figure 4–1. The Monitor Program branches program execution if an

interrupt occurs to the associated interrupt vector located in the second interrupt vector address range. The

instruction used is an absolute BR command (i.e., BR &0FFEAh for the ADC interrupt). Therefore, during

the use of the Monitor Program, the interrupt vectors are moved by an amount of FC00h below their normal

location.

Reset

NMI

P0.0 Interrupt

P0.1 Interrupt

Watchdog Interrupt

ADC Interrupt

Basic Timer Interrupt

Port0.2 to 0.7 Interrupt

FFFEh

Interrupt

FFE0h

Reset

NMI

P0.0 Interrupt

P0.1 Interrupt

Watchdog Interrupt

ADC Interrupt

Basic Timer Interrupt

Port0.2 to 0.7 Interrupt

03FEh

Interrupt

03E0h

Figure 4–1. Monitor Interrupts for the MSP430x32x Family

SLAS191A Datasheet(PDF) 63 Page - Texas Instruments