1. The Microprocessor-based PC System Prima Dewi Purnamasari Microprocessor Electrical Engineering Department University of Indonesia

2. What is Computer? Basically, there are 3 components to build a computer, and those three are interconnected with wires. Could you name it? Microprocessor (c) Prima Dewi Purnamasari 2011 2 ???

3. General Block Diagram of the PC Fig. 1.2 shows the general block diagram of the PC 3Microprocessor (c) Prima Dewi Purnamasari 2011

4. 4 Memory Microprocessor I/O BUS

5. MICROPROCESSOR Microprocessor (c) Prima Dewi Purnamasari 20115

6. The Microprocessor The microprocessor is the controlling element in a computer system and is sometimes referred to as the CPU (Central Processing Unit) Memory and I/O are controlled through instructions that are stored in the memory and executed by the microprocessor 6 Microprocessor (c) Prima Dewi Purnamasari 2011

7. The microprocessor performs three main tasks for the computer system: 1.Data transfer between itself and the memory or I/O systems 2.simple arithmetic & logic operations (Table 1.3) 3.program flow via simple decisions (Table 1.4) Microprocessor (c) Prima Dewi Purnamasari 2011 7 The Microprocessor

8. Microprocessor (c) Prima Dewi Purnamasari 20118

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10. The Microprocessor Why the microprocessor is powerful? – Able to execute millions of instructions per second from a program or software (group of instructions) stored in the memory system – able to make simple decision, based upon numerical facts (Table 1.4) 10 Microprocessor (c) Prima Dewi Purnamasari 2011

11. MEMORY Microprocessor (c) Prima Dewi Purnamasari 201111

12. Memory The memory system is divided into three main parts: – TPA (Transient Program Area) – system area, – XMS (Extended Memory System) (optional) 12 Microprocessor (c) Prima Dewi Purnamasari 2011

13. Memory System The first 1M byte of memory  the real/conventional memory system. Intel mP is designed to function this area in real mode of operation 80286  Pentium 4 contain not only real memory, but also extended memory The Pentium Pro-based computer system, for example, can have up to 1M less than 4G or 1M less than 64G of extended memory 13 Microprocessor (c) Prima Dewi Purnamasari 2011

14. Memory Address In Hexadecimal format 1MByte Real Memory: = 2 20 x 1 Byte = 1 0000 0000 0000 0000 0000 B x 1 Byte Each block of memory holds 1 Byte (8 bits) data 1MByte memory address: – Starting address (#1) : 00000H – Ending address (#2 20 ) : FFFFFH Microprocessor (c) Prima Dewi Purnamasari 2011 14

15. Trivia How if 2MByte Memory? What is the starting and ending address? Microprocessor (c) Prima Dewi Purnamasari 2011 15

16. Trivia How if 2MByte Memory? What is the starting and ending address? 2MB = 2 21 = 1 1111 1111 1111 1111 1111 (21 x 1) = 1FFFFF H Starting address = 000000H Ending address = 1FFFFFH Microprocessor (c) Prima Dewi Purnamasari 2011 16

17. Memory Illustration FFFFFH… …………… … … 00002H… 00001H0111 0001 B 00000H0AH Microprocessor (c) Prima Dewi Purnamasari 2011 17 Memory Address Each block of memory contains 1 Byte or 8 bits data

18. Microprocessor (c) Prima Dewi Purnamasari 201118 Memory System

19. Transient Program Area (TPA) Holds the OS and other program that control the computer system Stores any currently active or inactive application programs The length of TPA is 640 KB Microprocessor (c) Prima Dewi Purnamasari 2011 19

20. Memory map of TPA The memory map (fig. 1.4, in hexadecimal addr.) shows how many areas of the TPA are used for system programs, data, and drivers Microprocessor (c) Prima Dewi Purnamasari 2011 20

21. TPA The interrupt vectors access various features of the DOS, BIOS (Basic I/O System), and application The BIOS and DOS communications areas contain transient data used by program to access I/O devices and internal features of the computer system 21 Microprocessor (c) Prima Dewi Purnamasari 2011

22. TPA The IO.SYS is a program that loads into the TPA from the disk whenever an MSDOS or PC DOS system is started The MSDOS (PCDOS) program occupies two areas of memory The size of the driver area and # of drivers change from one computer to another Microprocessor (c) Prima Dewi Purnamasari 2011 22

23. TPA The COMMAND.COM program controls the operation of the computer from the keyboard when operated in DOS mode The free TPA area holds application programs as they are executed Microprocessor (c) Prima Dewi Purnamasari 2011 23

24. System Area The system area (Fig. 1.5) contains program on either a read-only memory or flash memory and also areas of read/write (RAM) memory for data storage Microprocessor (c) Prima Dewi Purnamasari 201124

25. EMS The area at locations C8000H- DFFFFH is often open or free. It is usually used for the Expanded Memory System (EMS)  Fig.1.6 The EMS allows a 64 KB page frame of memory to be used by application programs Microprocessor (c) Prima Dewi Purnamasari 201125

26. I/O Microprocessor (c) Prima Dewi Purnamasari 201126

27. Input Output (I/O) The input/output space extends from I/O port 0000H to port FFFFH. An I/O port is similar to a memory address but addresses an I/O device The I/O area contains two major sections (Fig 1.7): the area below I/O location 0500H is reserved for system devices the remaining area is available I/O space for expansion Microprocessor (c) Prima Dewi Purnamasari 201127

28. BUS Microprocessor (c) Prima Dewi Purnamasari 201128

29. Buses A bus is a set of common connections (wires ) that interconnect components in a computer system and carry the same type of information Function: 1.select an I/O or memory device 2.transfer data between an I/O device or memory and the microprocessor 3.control the I/O and memory system 29 Microprocessor (c) Prima Dewi Purnamasari 2011

30. BUSSES Three buses exist for the transfer of information: 1)address, 2)data, 3)control Microprocessor (c) Prima Dewi Purnamasari 2011 30

31. Buses (cont’d) The control bus contains lines that select the memory or I/O and cause them to perform a read or write operation. Four control bus connections: MRDC, MWTC, IORC, IOWC The address bus requests a memory location from the memory or an I/O location from the I/O devices 31 Microprocessor (c) Prima Dewi Purnamasari 2011

32. Buses (cont’d) Example the micro-instructions for READ: 1.the  p reads the contain of memory location by sending the memory an address through address bus 2.the  p sends the memory read control signal (MRDC) to cause memory to read data via control bus 3.the data read from the memory are passed to the microprocessor through the data bus 32 Microprocessor (c) Prima Dewi Purnamasari 2011

33. Buses (cont’d) The (maximum) memory sizes and organizations differ between various member of the Intel  p family Data bus size defines the amount of data can be transferred at a time (8, 16, 32, 64 bit) Address bus size corresponds to (maximum) memory size can be attached to the microprocessor Table 1.5 depicts a complete listing of bus and memory sizes on the Intel family of  p 33 Microprocessor (c) Prima Dewi Purnamasari 2011

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35. NUMBER SYSTEMS Self reading… Microprocessor (c) Prima Dewi Purnamasari 201135