Uploaded to ftp://ftp.devoresoftware.com/downloads, yes downloads, are
emm386.zip (executable) and emm386sr.zip (source) fixing two minor
problems with the official Tom Ehlert release of EMM386.  The files
are dated April 20, 2004.

This version of EMM386 supports EMS 4.0 function 58h, so that it EMS
will work with TDSK, and any other utility which might use function
58h.  Additionally, EMM386 now shadows the ROM at FC00-FFFFh plus
other stuff, to help some PC's which have problems rebooting via the
BIOS call.  You only really need this version of EMM386 if you use
TDSK with EMS or have another program which is having problems with
EMS, or if you use FDAPM or FDISK and their reboot commands.

In the first of the two changes, both the 0 and 1 subfunctions of EMS
4.0 function 58h dealing with mappable page counts and info are now
supported in EMM386.

In the second change, EMM386 now shadows the 16K ROM block at
FC00-FFFF so that it can modify instructions at the standard BIOS
reboot address of FFFF:0.  This is necessary because some BIOS's or
environments are not compatible with operating in V86 mode under the
EMM when rebooting the machine.  They crash the machine instead, and
not necessarily to a reboot condition.

Now what EMM386 does is shadow the ROM address with RAM (just like the
way UMB's work) and copy that original ROM block image to that RAM.
It then writes an INT 9 instruction at address FFFF:0 in the RAM
shadow memory, overwriting the original ROM instructions there.

EMM386 already has a special interrupt vector check for INT 9 keyboard
interrupt, so that it can catch Ctrl-Alt-Del keypresses.  When those
are detected, EMM386 reboots the machine either by port or by turning
off protected mode and memory mapping, then jumping to ROM image
address FFFF:0 in real mode.  In the latest revision, I added code so
that on entry to the V86 INT 9 handler, EMM386 checks to see if the
INT 9 came from address FFFF:0.  If so, it acts as if a Ctrl-Alt-Del
key sequence was pressed.

It's actually frightfully clever and I would be immoderately proud of
myself were it not for the piddling fact that I scavenged all the good
ideas from other code and people.