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Board Description and Memory Maps

Notes 1. For a complete description of the register bits, refer to the data sheet for the specific chip. For a more detailed memory map, refer to the following detailed peripheral device memory maps.

2.The SCC is an 8-bit device located on an MC2 chip private data bus. Byte access is required.

The data register of the Zilog Z85230 device which is interfaced by the MC2 chip ASIC cannot be accessed. The Zilog Z85230 has an indirect access mode to the data registers which is functional and must be used.

3.Writes to the LCSR in the VMEchip2 must be 32 bits. LCSR writes of 8 or 16 bits terminate with a TEA signal. Writes to the GCSR may be 8, 16 or 32 bits. Reads to the LCSR and GCSR may be 8, 16 or 32 bits. Byte reads should be used to read the interrupt vector.

4.This area does not return an acknowledge signal. If the local bus timer is enabled, the access times out and is terminated by a TEA signal.

5.Size is approximate.

6.Port commands to the 82596CA must be written as two

16-bit writes: upper word first and lower word second.

7.Refer to the Flash and PROM Interface section in the MC2 chip description in Chapter 3.

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Motorola MVME172 manual Board Description and Memory Maps