Buses Flashcards
What are buses?
pathways used to send data around the processor.
What are the main buses?
control bus
data bus
address bus
characteristics of a control bus
it is used by CPU to communicate with other devices and components carrying commands and returning status signals
characteristics of a data bus
carries data/information from one register to the other between the processor and the memory
characteristics of an address bus
carries the address of the memory location being read or written to
what bus would be used between the CPU and main memory when MAR needs the instruction address
address bus
what bus would be used to get the instruction data to MDR from main memory
a data bus
what bus would be used between acc and the main memory after instruction execution
control bus
is the data bus bidirectional?
yes
is the control bus bidirectional?
yes
is the address bus bidirectional?
no, it only receives
What are some control signals?
- bus request : indicates request use of data bus by a device
- bus grant - device can use data bus
- memory write
- memory read
- interrupt request - device is requesting attention
What is a word?
a unit of memory of one address
What does PCI stand for?
peripheral component interconnect
What is PCI
bus where most components and buses are connected to in modern computers
