By default, the IRQ for the floppy disk controller is IRQ 6.
A floppy disk typically uses IRQ6 (that is on windows server 2003)
IRQ 14
6
if your refering to IDE or SATA controller mostly likely using IDE or Sata ports on the board else u could go external by USB disk controller is recognised in BIOS under an IRQ
IRQ 1 is used exclusively for the keyboard controller.
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
14
The controller decides whether the CPU should be immediately notified of that IRQ or not and to translate the IRQ number into an interrupt vector (i.e. a number between 0 and 255) for the CPU's table.
The controller decides whether the CPU should be immediately notified of that IRQ or not and to translate the IRQ number into an interrupt vector (i.e. a number between 0 and 255) for the CPU's table.
CPU
The CPU has its own internal bus for communication the internal cache
From http://www.brainbell.com/tutors/A+/Hardware/Direct_Memory_Access_DMA.htm "DMA channels use the same rules as IRQs. Just as with the 8259 chip, DMA availability soon became a problem because an insufficient number of channels was available. A second DMA chip was added for 286-based computers. Just like the second IRQ chip, these two are cascaded, allowing a total of eight DMA channel assignments (usually referred to simply as DMA channels). The floppy disk drives on all computers use DMA channel 2."