MVME177 Functional Description

Local bus time-out

Note The time basis for all local resources is set by Prescaler

register(s). Refer to the Single Board Computers Programmer's Reference Guide for detailed programming information.

Programmable Tick Timers

Four 32-bit programmable tick timers with 1 s resolution are provided:

Two in the VMEchip2 and

Two in the PCCchip2

The tick timers can be programmed to generate periodic interrupts to the processor. Refer to the VMEchip2 and PCCchip2 in the Single Board Computers Programmer's Reference Guide for detailed programming information.

Watchdog Timer

A watchdog timer function is provided in the VMEchip2. When the watchdog timer is enabled, it must be reset by software within the programmed time or it times out. The watchdog timer can be programmed to generate:

A SYSRESET signal

Local reset signal, or

Board fail signal if it times out

Refer to the VMEchip2 in the Single Board Computers Programmer's Reference Guide for detailed programming information.

Software-Programmable Hardware Interrupts

Eight software-programmable hardware interrupts are provided by the VMEchip2. These interrupts allow software to create a hardware interrupt. Refer to the VMEchip2 in the Single Board Computers Programmer's Reference Guide for detailed programming information.

4

4-17

Page 69
Image 69
Motorola MVME177 manual Programmable Tick Timers, Watchdog Timer, Software-Programmable Hardware Interrupts