Transcript Lab3 for I/O

Lab3 for I/O
TA:黃俊輔 jojoman
email:[email protected]
Handshaking
http://rebrown.com/rebrown/handsh.htm
I/O Driven
• Busy waiting
• Interrupt
• DMA (Direct Memory Access)
I/O Driven
• Busy waiting
Keep asking I/O device if they have
data to transfer or not.
I/O Driven
• DMA (Direct Memory Access)
Short for DMA, a technique for
transferring data from main memory
to a device without passing it
through the CPU.
IRQ Numbers
• IRQ#
0
1
2
3
4
5
Device
System timer
Keyboard
Cascade from IRQ 9
COM port 2
COM port 1
Parallel (printer) port 2
or sound cards
IRQ Numbers
• IRQ#
6
7
8
9
10
11
12
Device
Floppy drive controller
Parallel (printer) port 1
Real time clock
Open
Open
Open
PS/2 mouse
IRQ Numbers
• IRQ#
13
14
15
Device
Coprocessor
Primary IDE controller
(hard drives)
Secondary IDE controller
(hard drives)
Plug-and-Play(PnP)
• Plug-and-Play automatically tells the
software (device drivers) where to
find various pieces of hardware
(devices) such as modems, network
cards, sound cards, etc.
Plug-and-Play(PnP)
• PnP allocates the following "busresources" to both drivers and
hardware: I/O addresses, memory
regions, IRQs, DMA channels (ISA
bus only).
Assign a IRQ Number
• In win98 & win ME
click “系統” and open “裝置管理員”
• In win 2k & win XP
the same but...........
IRQ Conflicts
• There are few IRQ numbers open,
but we still have a lot of devices such
as USB, AGP, PCI, RAID, SATA, LAN,
1394.
• Solution: We have to share IRQ
numbers. It depends on each
motherboard.
IRQ Conflicts
• Example: for ABIT KT7A-Raid
Device
A
B
C
D
PCI Slot1
s
PCI Slot2
s
PCI Slot3
s
PCI Slot4
s
PCI Slot5
s
PCI Slot6
s
AGP Slot
s
USB controller s
RaidController s
-
Lab Question1
• How to change keyboard’s repeat
delay and repeat rate?
Lab Question2
• How to setup/add/switch input
methods?
Lab Question3
• Adjustable on “control panel”