03-10-2012, 05:52 PM
THE 8088 AND 8086MICROPROCESSORS ANDTHEIR MEMORY ANDINPUT/OUTPUT INTERFACES
THE 8088 AND 8086.ppt (Size: 2.21 MB / Downloads: 71)
The 8088 and 8086 Microprocessors
The 8086, announced in 1978, was the first 16-bit microprocessor introduced by Intel Corporation
8086 and 8088 are internally 16-bit MPU.
Externally the 8086 has a 16-bit data bus and the 8088 has an 8-bit data bus
8086 and 8088 both have the ability to address up to 1 Mbyte of memory and 64K of input/output port
The 8088 and 8086 are both manufactured using high-performance metal-oxide semiconductor (HMOS) technology
The 8088 and 8086 are housed in a 40-pin dual inline package and many pins have multiple functions
Minimum-Mode Interface
Address/Data bus
The address bus is used to carry address information to the memory and I/O ports
The address bus is 20-bit long and consists of signal lines A0 through A19
A 20-bit address gives the 8088 a 1 Mbyte memory address space
Only address line A0 through A15 are used when addressing I/O.
This give an I/O address space of 64 Kbytes
The 8088 has 8 multiplexed address/data bus lines (A0~A7)
8086 has 16 multiplexed address/data bus lines (A0~A15)
Maximum-Mode Interface
The maximum-mode configuration is mainly used for implementing a multiprocessor/coprocessor system environment
Multiple processors exist in the system
Each executes its own program
Global resources and local resources
The former are common to all processors
The latter are assigned to specific processors
In the maximum-mode, facilities are provided for implementing allocation of global resources and passing bus control to other microprocessors sharing the system bus
System Clock
PCLK and OSC signals
The peripheral clock (PCLK) and oscillator clock (OSC) signals are provided to drive peripheral ICs
The clock output at PCLK is half the frequency of CLK. The OSC output is at the crystal frequency which is three times of CLK