Motorola MVME1X7P manual Flash Memory on the MVME177

Models: MVME1X7P

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Programming Interfaces

MVME177

The EEPROMs on the MVME177 share 2MB of memory with the first 2MB of Flash memory. The EEPROM can co-exist with 2MB of Flash, or you may wish to program all 4MB as Flash memory. The Flash and EEPROM configuration is jointly controlled by a configuration switch (S4) as described in Chapters 1 and 4 of MVME177P Single Board Computer Installation and Use, and by control bit GPIO2 in the VMEchip2 ASIC, as described in Chapter 2, VMEchip2.

The EPROMs are mapped to Local Bus address 0 following a Local Bus reset.This allows the MC68060 processor to access the reset vector and execution address following a reset.

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Flash Memory on the MVME177

The MVME177 includes four 28F008SA Flash memory devices. The 32- bit wide Flash can support 8-, 16-, and 32-bit accesses. The Flash can be used for the onboard debugger firmware, which can be downloaded from I/O resources such as Ethernet, SCSI, serial port, or VMEbus. Flash write- protection is programmable by setting a control bit (GPIO bit 1) in the VMEchip2 GPIO register after downloading.

When the Flash memory is used with EEPROM, only the top or bottom 2MB of Flash memory is visible at any one time. For access to the shadowed area of Flash, the 177Bug firmware provides the SFLASH command.

The MVME177 is shipped with the top 2MB of Flash memory and

EEPROM mapped as illustrated by Map 2 in Figure 1-3.

The 177Bug is shipped in EEPROM. To map all 4MB of Flash and retain access to the 177Bug, perform the following steps:

1.Map Flash and EEPROM as shown in Map 3 in Figure 1-3.

2.Copy the 177Bug into the bottom 2MB of Flash memory.

3.Remap Flash memory as shown in Map 1 in Figure 1-3.

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Motorola MVME1X7P manual Flash Memory on the MVME177