1

Board Level Hardware Description

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.

4.This area does not return an acknowledge signal. If the processor bus timeout 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.DROM (BOOT ROM) appears at $0 following a local peripheral bus reset. The DROM appears at 0 until the DR0 bit is cleared in the PCCchip2. The DR0 bit is located at address 0 bit D15. The DROM must be disabled at 0 before the DRAM is accessed.

VMEbus Memory Map

This section describes the mapping of local resources as viewed by VMEbus masters.

VMEbus Accesses to the Local Peripheral Bus

The VMEchip2 includes a user-programmable map decoder for the VMEbus to local peripheral bus interface. The map decoder allows the user to program the starting and ending address and the modifiers the MVME197LE responds to.

VMEbus Short I/O Memory Map

The VMEchip2 includes a user-programmable map decoder for the GCSR (Global Control and Status Registers). The GCSR map decoder allows the user to program the starting address of the GCSR in the VMEbus short I/O space.

1-16

Installation Guide

Page 32
Image 32
Motorola MVME197LE manual VMEbus Memory Map, VMEbus Accesses to the Local Peripheral Bus, VMEbus Short I/O Memory Map