Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!tut.cis.ohio-state.edu!snorkelwacker!bloom-beacon!eru!hagbard!sunic!ericom!tnetxa.ericsson.se!etxsral From: etxsral@tnetxa.ericsson.se (Lars Nilsson, ERICSSON TELECOM, SWEDEN) Newsgroups: comp.windows.ms Subject: Re: Mouse on Com3?? Message-ID: <18829@tnetxa.ericsson.se> Date: 14 Sep 90 22:16:18 GMT References: <1990Sep8.225702.6638@portia.Stanford.EDU> Lines: 33 In article , otto@tukki.jyu.fi (Otto J. Makela) writes: > The IRQ line number can be calculated simply from the interrupt vector number > by substracting 8 (remember, the first hardware interrupt is timer0 on IRQ0, > which produces interrupt 8). The 8259A interrupt controller mask could > actually also be simply calculated from the IRQ by shifting one left IRQ# > bits and doing a logical not to the result; seems that a programmer at > MicroSoft felt that it's easier to do it this way. > > Now, to patch your own values into this table, you need to know the same > things about the COM port which you intend to use as your mouse port: the > 8250 chip address and the interrupt it generates. > > For your convinience, here are two common methods of arranging COM3 and COM4: > COM3 03E8h 0Ch 4 EFh=11101111b > COM4 02E8h 0Bh 3 F7h=11110111b My computer uses IRQ 10/IRQ 11 for COM3/COM4. Is it still possible to patch the mouse.drv ? ---- Lars Nilsson Ericsson Telecom AB , Sweden Phone: + 46 (8) 719 7308 Fax: + 46 (8) 645 60 76 INTERNET: etxsral@tnetxa.ericsson.se FIDONET : Lars Nilsson at 2:201/108.7 Ericsson Corporate Network: VAX-MAIL: TNETXA::ETXSRAL MEMO: ERI.ETX.ETXSRAL IBM : ETXSRAL at LMEL ETXSRAL at LMES