What is the standard IRQ setting for a math coprocessor?
IRQ 1
14
4
This interrupt is the first choice that most sound cards make when looking for an IRQ setting.
IRQ 1 is used exclusively for the keyboard controller.
IRQ
IRQ 0 - System timer. IRQ 1 - Keyboard. IRQ 2 - Cascaded signals from IRQs 8-15. IRQ 3 - COM2 (Default) and COM4 (User) serial ports IRQ 4 - COM1 (Default) and COM3 (User) serial ports IRQ 5 - LPT2 Parallel Port 2 or sound card IRQ 6 - Floppy disk controller IRQ 7 - LPT1 Parallel Port 1 or sound card (8-bit Sound Blaster and compatibles) IRQ 8 - Real time clock IRQ 9 - Free / Open interrupt / Available / SCSI. Any devices configured to use IRQ 2 will actually be using IRQ 9. IRQ 10 - Free IRQ 11 - Free IRQ 12 - PS/2 connector Mouse. IRQ 13 - ISA / Math Co-Processor IRQ 14 - Primary IDE. If no Primary IDE this can be changed IRQ 15 - Secondary IDE These are just a set of standard IRQs. For much more detail check our Ralf Brown's list located at http://www.cs.cmu.edu/~ralf/files.html
IRQ 3.
LTP1 should use IRQ7.
By default, the IRQ for the floppy disk controller is IRQ 6.
By default IRQ 7 is assigned to LPT1.
From: http://www.techadvice.com/tech/C/ComPort_TS.htmCom1, IRQ 4, address: 3F8Com2, IRQ 3, address: 2F8Com3, IRQ 4, address: 3E8Com4, IRQ 3, address: 2E8