Xref: utzoo comp.unix.xenix:7165 comp.unix.questions:15735 Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!bloom-beacon!usc!cs.utexas.edu!uunet!ispi!jbayer From: jbayer@ispi.UUCP (Jonathan Bayer) Newsgroups: comp.unix.xenix,comp.unix.questions Subject: Re: Using internal modem cards with SCO Xenix Message-ID: <1112@ispi.UUCP> Date: 17 Aug 89 12:53:51 GMT References: <958@lakesys.UUCP> <5101@viscous.sco.COM> Reply-To: jbayer@ispi.UUCP (Jonathan Bayer) Followup-To: comp.unix.xenix Organization: Intelligent Software Products, Inc. Lines: 37 In article <5101@viscous.sco.COM> rosso@sco.com (Ross Oliver) writes: }The reason you are having problems is that your internal modems cannot }be set to use interrupts other than IRQ3 or IRQ4. For a serial device }to work under XENIX, it must be configured on its own interrupt vector. }IRQ4 is allocated to COM1, and IRQ3 is for COM2. Since MS-DOS does not }use interrupts, manufacturers of serial cards have taken the I/O ports }used by COM1 and COM2, and simply extended them on up through the I/O }space, thus producing COM3, COM4, COM5, etc. (I've seen some cards that }claim to go up to COM10). However, since XENIX requires interrupts as }well as the I/O ports, most of these modems and serial cards won't work }under XENIX above COM2. } }However, if you can set these boards to use other interrupts, then you }can use them alongside existing COM1 and COM2 devices. To do this, you }will have to modify the /usr/sys/conf/master file to tell the serial }driver to handle the additional interrupts. Modify the "vec3" and "vec4" }columns for the "sio" entry, then rebuild your kernel. OK. Since each device must have it's own interrupt, why not make two serial ports both use the same interrupt, and modify sioconf.c to show that the second serial port is nothing more that a second port on the first serial card? For these serial cards that go to com 10 (or whatever), why not simply set up all the ports on the card to use the same interrupt, and set up sioconf properly (specificaly the port count, the interrupt vector, the base address of the board, the interrupt poll address, and the spacing of the io ports on the board). The only potential problem is the interrupt poll address (as I see it) JB -- Jonathan Bayer Beware: The light at the end of the Intelligent Software Products, Inc. tunnel may be an oncoming dragon 500 Oakwood Ave. ...uunet!ispi!root Roselle Park, NJ 07204 (201) 245-5922 jbayer@ispi.UUCP