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Re: Laptop //c
Roger Johnstone wrote:
In <qOidnYpWKIwNC57ZnZ2dnUVZ_tydnZ2d@comcast.com> Michael J. Mahon wrote:
julian814 wrote:
I might want to sail into uncharted waters with the memory. The
Service Manual says the memory can be expanded to 16 meg, but I'd
think that with current flash technology, that could be upped even
further. Granted, software converted over to Newton OS is
considerably smaller, but the more I can get this thing to do, the
better.
Flash memory is more like disk than RAM.
The standard eMate has 1MB of DRAM (used for running software) and 2MB
of flash RAM (used for program and data storage), plus 8MB of ROM
holding the operating system and various applications. There is an
internal expansion slot which can take a memory upgrade card for both
DRAM and flash. I can't remember if Apple ever sold one but there were
third-party ones available.
Ah, the "original" flash memory, more like EEPROM.
You can also add extra flash memory via the external PC Card slot.
Unfortunately the OS is only capable of handling linear flash memory,
which is almost impossible to get now. Most modern memory cards have a
controller between the computer and the memory so it appears as a block
storage device. There is a commercial driver available which allows a
Newton to use ATA flash memory (normally CompactFlash cards in a PC Card
adapter) for storage.
Still, this driver must simply "page in" software to RAM to execute,
so the ATA flash is very much a "virtual disk".
Fortunately, it shouldn't be a problem in the intended application.
1MB is plenty for an emulator, and if a larger IIc "RAM" is needed,
it can be swapped in and out of a paging area in RAM from/to the
ATA flash memory at a negligible cost in speed whenever an emulated
bank switch is done.
-michael
Music synthesis for 8-bit Apple II's!
Home page: http://members.aol.com/MJMahon/
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