Re: TI-H: DriverLESS Memory Expander
[Prev][Next][Index][Thread]
Re: TI-H: DriverLESS Memory Expander
At 08:59 PM 11/16/97 -0700, Grant Stockly wrote:
>Well, that wouldn't add more than about 32k. The rom in the calcs doesn't
>even support more than that. It would take a long time, and your warntee
>would void.
>
>>what about adding directly to the existing memory in the calc so that it
uses
>>the existing MAP.? Im surprised nobody has devised a lan to take care of
>>that.
Actually it would be impossible. The ROM is addressed in from $0000-$3FFF
for page 0 and $4000 to $7FFF for pages 1 to 7. The RAM is addressed from
$8000 to $FFFF (including stack and video mem). Because the Z80 can only
use 16-bit addresses that's all the memory it can address. The TI-86 uses
RAM pages, but this would be impossible on the 85 because even if you added
it, the ROM wouldn't support it.
--
Brian Leech
butvis@mindspring.com
ICQ UIN: 1355611
References: