What Is REX
REX is completely plug and play flash memory upgrade. REX plugs into the Option ROM slot, with no soldering or necessity to open the laptop case.
Rex provides support for up to 8 in-circuit selectable option roms. That means, you can have 8 different software packages on one Option ROM, and select between them without physically unplugging anything.
In addition, REX is in-circuit, software reprogrammable. That means you can change replace an Option ROM image without any special hardware or physically unplugging REX.
An integrated REX ROM houses the release 1 REX Manager software. REX Manager allows you to pick which of the 8 ROM images is the one currently in use.
REX Manager operates "behind the scenes" to make sure the currently selected Option ROM image is automatically enabled on every power cycle. This is an impressive trick since REX does not receive power while the laptop is off (unlike the RAM memory circuit).
Also, REX is able to do this without using up any precious RAM space!
Advanced Main ROM Replacement Mode
For users that with the do-it-yourself spirit, an optional feature of REX can be enabled.
With a single wire soldered in place, REX permits Main ROM replacement!
This means that you can disable the hard coded ROM on your motherboard and replace it with a specific block of the 1MB of flash that is dedicated to act as if it was the Main ROM. So, you can upgrade your OS with little tweaks like Y2K, the lomem patch, new character sets, and other things that get dreamed up.
Installing REX Manager
From a cold restart, simply typing
will install the REX system.
To start REX Manager, press reset and hold the ESC key. Then from basic type:
REX Manager will start, allowing you to manage which ROMs stored in REX can be used, and when.
A separately loadable utility will allow you to burn rom images into REX.
Future releases of REX will have a built in file system for managing REX files, TPDD files and RAM files.
There will be approx. 512K of file storage.