Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ames!nrl-cmf!mailrus!uflorida!gatech!hubcap!rwberry From: rwberry@hubcap.UUCP (Robert W Berry) Newsgroups: comp.os.minix Subject: Re: Minix EMS Ramdisk Summary: EMS implementation problems Message-ID: <3004@hubcap.UUCP> Date: 20 Sep 88 03:13:18 GMT References: <1365@ucsfcca.ucsf.edu> Organization: Clemson University, Clemson, SC Lines: 28 One nasty side of implementing a EMS RAMDISK (or more CORE MEMORY with the EMS 4.0 spec) is that there are about 75 different makes of EMS expansion cards on the market. And while they all provide the same EMS interface to DOS, the way the LIM standard is implemented differs slightly from card to card. Like you, I have an AST card, and with the EEMS hardware on this card, it's perfect to swap procs in and out of the address space. Unfortunately, the people at AST have been a little less than helpful in letting me know how their (my) card works. Alas, without knowing how the card works below the level of the device driver, it's going to be difficult to write an EMS (EEMS??) driver for MINIX. A while back people got a EMS ramdisk going on AT-class machines, but only with the help of the AT ROM BIOS, which had an interrupt service perfectly suited to copying blocks of text in and out of EMS. No such luck on the PC cards. There is a glimmer of hope, however. Some clone manufacturers (sp?) are now putting LIM 4.0 hardware on their motherboards. This may still not be a standard, but it least it's a little easier to get info on. If anyone out there knows more about this, PLEASE JOIN IN. Particularly about the AST cards, I could probably come up with a driver, if only I knew how to program the doggone things. Bob -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=- Bob Berry -=- PC-Guru's Inc. ! Compuserve:72646,3331 or 73170,1242 -=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-= ! BITNET:rwberry@clemson -=- -=- This space for rent or lease ! INTERNET:rwberry@hubcap.clemson.edu -=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-