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What is 1 + 3?
The expansion bus connects to _______
Either the Northbridge or the Southbridge or both.
in modern PC's the system crystal does this:
it mainly pushes the CPU, RAM, and Chipset
This determines the speed of the expansion bus:
The Expansion bus Crystal
The original Expansion Bus Crystal's speed
The original expansion bus
The PC Bus, or XT Bus
Who invented the PC Bus?
IBM Invented it.
IBM Stands for:
International Business Machines
Stats for the original PC Bus:
8 bits wide / 7Mhz / Manual configuration
Advanced Technology Bus,
invented by IBM, named after the computer it was first used in. it was an extension to the PC BUS.
16 bits wide / 7Mhz / Manual configuration
Industry Standard Architecture
industry standard architecture Bus
A pool of PC-bus clone makers pooled there knowledge of the IBM buses and invented the ISA BUS
ISA BUS STATS
16bit wide / 7Mhz / Manual Configuration
The 3 False starts at replacing the ISA BUS
IBM Micro Channel Architecture (MCA)
Extended ISA (EISA)
Vesa Local Bus (VL-BUS)
IBM Micro Channel Architecture (MCA)
An attempt at replacing ISA, but it proved too expensive.
An attempt at replacing the ISA BUS, but it proved too expensive.
Vesa Local Bus (Video Electronic standards association.
An attempt at replacing the ISA BUS.
PCI (4 items)
1. Stands for Peripheral Component Interconnect
2. Developed by Intel
3. 32 bits wide / 33 Mhz / Auto config(PnP)
4. Allows for multiple types of buses.
1. Accelerated Graphics Port
2. A Special PCI slot that connects directly to the northbridge
2. Seen mostly only in very high end systems like servers.
3. 64bit wide bus.
PCI-X Speeds (4)
PCI IN A SMALL FORM FACTOR FOR LAPTOPS, THE CARD LAYS FLAT.
What does PCIe connect to?
It connects directly to the northbridge
what kind of connection does PCIe use?
point to point serial connection, using its on bus.
What are Lanes?
Lanes are the two wires used by PCIe to communicate with the northbridge one lane receives while the other sends.
what speed do PCIe lanes run at?
2.5 or 5 Gbs
How many point-to-point connections can a PCIe card use? What is its bandwidth? What is most common?
Theoretically 320 Gbs Bandwidth
x1 or x4 is common for general use.
video cards usually use x16
communication is the same as
System resources (4)
I/O Addresses are listed in this way?
they are listed in the device manager as Hex Values.
This is how a device gets the CPU's attention.
Devices send an IRQ on this wire
1. Programable Interrupt Controller
2. A now obsolete: a traffic controller for IRG's
3. Only supports 15 IRQ's
1. I/O Advanced Programable Interrupt Controller
2. Usually built into the southbridge
3. This recieves the IRQ's from devices the charges the INT wire to the Processor.
This is the IRQ belonging to the IOAPIC
-preset combinations of I/O Addresses for the serial ports
-preset combinations of I/O Addresses for the parallel ports
COM1 = IRQ4
COM2 = IRQ3
COM3 = IRQ4
COM4 = IRQ3
LPT1 = IRQ7
LPT2 = IRQ5
DIRECT MEMORY ACCESS
THIS IS USED WHEN A DEVICE ACCESSES MEMORY DIRECTLY. MOST COMMON IN LAPTOPS
ALSO KNOWN AS THE 8237
HANDLES ALL DMA FUNCTIONS
ASSIGNS DMA CHANNELS TO DEVICES
DEVICES WITH BUILT IN CIRCUITRY THE USE DMA WITHOUT THE NEED OF A DMA CONTROLLER
DOES PCI/PCIe USE DMA?
NO, THEY DO NOT USE DMA.
MEMORY ADDRESSES FOR CARDS
SOMETIMES A CARD WILL NEED MEMORY ADDRESSES SO THAT THE CPU CAN ACCESS ITS ONBOARD MEMORY. THIS IS AUTOMATIC.
THIS USED TO BE THE WINDOWS
HARDWARE COMPATIBILITY LIST. NOW IT IS THE WINDOWS LOGO'D HARDWARE LIST.
WINDOWS HARDWARE QUALITY LABS, WHERE DRIVERS GET THE MICROSOFT SIGNED STATUS
64 BIT WINDOWS WILL NOT LET YOU DO THIS?
INSTALL UNSIGNED DRIVERS
WHAT MAINLY USES DMA ON MODERN SYSTEMS?
A RED X IN DEVICE MANAGER MEANS WHAT?
THE DEVICE HAS A BAD CONNECTION, OR A BAD DRIVER, OR ITS A BAD CARD.