Functional Description

Watchdog Timer

The VMEchip2 ASIC supplies a watchdog timer function. When enabled, the watchdog timer must be reset by software within the programmed interval or it times out. The watchdog timer can be programmed to generate a SYSRESETsignal, a local reset signal, or a board fail signal if it times out. Refer to Chapter 2, VMEchip2 for detailed programming information.

Software-Programmable Hardware Interrupts

The VMEchip2 ASIC supplies eight software-programmable hardware interrupts. These interrupts allow software to create a hardware interrupt. Refer to Chapter 2, VMEchip2 for detailed programming information.

Local Bus Timeout

The MVME167P and MVME177P single-board computers provide a timeout function in the VMEchip2 ASIC for the Local Bus. When the timer is enabled and a Local Bus access times out, a Transfer Error Acknowledge (TEA) signal is sent to the Local Bus master. The time-out value is selectable by software for 8 μsec, 64 μsec, 256 μsec, or infinite. The Local Bus timer does not operate during VMEbus bound cycles.

VMEbus bound cycles are timed by the VMEbus access timer and the VMEbus global timer. Refer to Chapter 2, VMEchip2 for detailed programming information.

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Functional Description

This section highlights a few specific features of the MVME1X7P single- board computers. For a complete functional description of the major blocks of the MVME1X7P, refer to the Installation and Use manual.

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Motorola MVME1X7P Functional Description, Watchdog Timer, Software-Programmable Hardware Interrupts, Local Bus Timeout