Path: utzoo!utgpu!water!watmath!clyde!rutgers!ames!amdahl!oliveb!felix!dhw68k!bob From: bob@dhw68k.cts.com (Bob Best) Newsgroups: comp.os.minix Subject: Re: TTY driver bugs/questions Keywords: EGA Message-ID: <4348@dhw68k.cts.com> Date: 17 Jan 88 17:08:26 GMT References: <2492@encore.UUCP> Reply-To: bob@dhw68k.cts.com (Bob Best) Organization: Wolfskill residence; Anaheim, CA (USA) Lines: 44 In article <2492@encore.UUCP> paradis@encore.UUCP (Jim Paradis) writes: > >(3) Biggest boo-boo of all: Apparently, my console driver doesn't >work on EGAs. Since the only machine I could test this on has a >cheap CGA, I just sort of prayed that it would work on an EGA as >well. Could someone out there fill me in on how to set up an EGA >for CGA emulation, and on the deficiencies in said emulation mode? > I was able to support EGA by using the simple fix provided previously for Minix. Specifically, I removed the code in con_init() that sends video parameters to the CGA (see under "Initialize the 6845"). I then added the following: in the #define section - #define EGA_ADDR_PORT 0x3c4 #define EGA_DATA_PORT 0X3c5 in con_init() - port_out(EGA_ADDR_PORT, 4); port_out(EGA_DATA_PORT, 1); This fix has solved my EGA problems. What I have noticed during brief testing of the tty driver is a problem involving response lag to tty input when I am running in multiuser mode. If I have a process running on the serial terminal that continuously outputs data to the terminal, I notice that the response to keyboard input from the console takes in excess of 5 seconds! Also, if I have processes running simultaneously on serial terminal and console that are continuously outputting data, a Ctrl-S from the serial terminal might require up to 20 seconds to suspend scrolling while at other times the response is immediate in a seemingly random pattern. I am currently in the process of trying to isolate this, but any help from Jim Paradis or someone else in the know would be appreciated. The Paradis tty driver is a marvelous achievement for which I am extremely grateful. Many thanks, Jim, for the time and effort. I really do appreciate the opportunity of having the entire source code to a fully functional multiuser operating environment to tinker with. -- Bob Best uucp: ...{trwrb,hplabs}!felix!dhw68k!bob InterNet: bob@dhw68k.cts.com