RadiSys EPC-5A, Hardware & Software Reference Manual

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EPC-5A Hardware & Software Reference Manual
Page C-6
C C
System BIOS recovery operates in detail as follows:
1. The boot block prepares the system hardware (DMA and interrupt controllers,
DRAM, etc.) to boot the recovery floppy.
2. The boot block loads the special boot sector on the recovery diskette (written to
the diskette by MAKEBOOT.EXE - a special Phoenix-supplied MS-DOS tool)
and jumps into it.
3. The boot sector loads MINIDOS.SYS from the floppy and jumps into it. This file
implements a very small set of MS-DOS functions that allow reading and writing
the FAT file system on the recovery diskette.
4. MINIDOS.SYS then loads PHLASH.EXE, which in turn reads PLATFORM.BIN
(customized for the EPC-5A) and BIOS.ROM from the floppy.
5. PHLASH.EXE uses the information and code in PLATFORM.BIN to properly
erase and program the FBD with the FBD data in BIOS.ROM.
Note that the recovery floppy diskette cannot be duplicated using a file by file copy
method but rather by a sector by sector method (such as MS-DOS’ s
DISKCOPY.EXE). The latter method also copies the special boot sector required by
the recovery process. If the boot sector is not copied correctly or is somehow
corrupted, the recovery process does not function correctly. The boot sector is not
required, however, for updates.
Reflashing using REFLASH.EXE
The FBD can also be reprogrammed using the RadiSys MS-DOS

utility
REFLASH.EXE. This is a flash read/modify/write utility that is useful for
reprogramming the entire FBD or programming a single BIOS extension into the FBD
while leaving the rest of it intact. REFLASH.EXE is an MS-DOS

only program and
cannot be executed with any memory managers loaded. REFLASH.EXE version 2.4
and above makes an INT15 call to attempt to control the write protect mechanism for
the FBD. The system supports this interface by manipulating the FBD write
protection in the chipset.
Reflash reprograms the blocks of the flash device specified on the command line.
Files-to-be-flashed are specified by using the /F=<filename> /O=<offset> [/P=<base
address>] command line parameters. Files are copied into the target device from low
to high memory addresses. Multiple files can be flashed in one Reflash invocation,
but each file must be followed by an offset and base address parameter.