2

VMEchip2

VMEbus Bus to Local Bus Interface:

Programmable VMEbus map decoder.

Programmable AM decoder.

Programmable local bus snoop enable.

Simple VMEbus to local bus address translation.

8-bit, 16-bit and 32-bit VMEbus data width.

8-bit, 16-bit and 32-bit block transfer.

Standard and extended VMEbus addressing.

Software-enabled write posting mode.

Write post buffer (17 four-bytes in BLT mode, two four-bytes in non-BLT mode).

An eight four-byte read ahead buffer (BLT mode only).

32-bit Local to VMEbus DMA Controller:

Programmable 16-bit, 32-bit, and 64-bit VMEbus data width.

Programmable short, standard, and extended VMEbus addressing.

Programmable AM code.

Programmable local bus snoop enable.

A 16 four-byte FIFO data buffer.

Supports up to 4 GB of data per DMA request.

Automatically adjusts transfer size to optimize bus utilization.

DMA complete interrupt.

DMAC command chaining is supported by a singly-linked list of DMA commands.

VMEbus DMA controller requester:

Software-enabled fair request modes;

Software-configured release modes:

Release-On-Request (ROR), and

Release-On-End-Of-Data (ROEOD);

Software-configured BR0-BR3 request levels; and

Software enabled bus-tenure timer.

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Motorola MVME172 manual VMEchip2