30-01-2012, 04:55 PM
Microprocessor Fundamentals Course
Introduction
A microprocessor systems course is commonly viewed as an essential component of computer engineering programs, as well as many electrical engineering programs. Such a course is often a student's first real initiation into a ``systems'' type course, where emphasis is not on analysis and formulas, but on understanding the design and operation of a real system at many levels of abstraction. The style and format of such a course represents a challenge for instructors.
The purpose of these lectures is to relate our views on this type of course, to describe how we offer the course at our institution, and to assess the effectiveness of our course. Key aspects of our approach include:
Memory
The memory section usually consists of a mixture of RAM (Random Access Memory) and ROM (Read Only Memory). It may also have magnetic floppy disks, magnetic hard disks, or optical disks (CDs, DVDs). Memory has two purposes. The first purpose is to store the binary codes for the sequences of instructions you want the computer to carry out. When you write a computer program, what you are really doing is writing a sequential list of instructions for the computer. The second purpose of the memory is to store the binary-coded data with which the computer is going to be working. This data might be the inventory records of a supermarket, for example.
Input/Output
The input/output or I/O section allows the computer to take in data from the outside world or send data to the outside world. Peripherals such as keyboards, video display terminals, printers, and modems are connected to the I/O section. These allow the user and the computer to communicate with each other. The actual physical devices used to interface the computer buses to external systems are often called ports. Ports in a computer function Just as shipping ports do for a count. An input port allows data from a keyboard, an A/D converter, or some other source to be read into the computer under control of the CPU.
Data Bus
The data bus consists of 8, 16, or 32 parallel signal lines. As indicated by the double-ended arrows on the data bus line in Figure 1, the data bus lines are bidirectional. This means that the CPU can read data in from memory or from a port on these lines, or it can send data out to memory or to a port on these lines. Many devices in a system will have their outputs connected to the data bus, but only one device at a time will have its outputs enabled. Any device connected on the data bus must have three-state outputs so that its outputs can be disabled when it is not being used to put data on the bus.
Hardware, Software, and Firmware
When working around computers, you hear the terms hardware, software, and firmware almost constantly. Hardware is the name given to the physical devices and circuitry of the computer. Software refers to the programs written for the computer. Firmware is the term given to programs stored in ROMs or in other devices which permanently keep their stored information.
Peripheral Interface Categories:
We can classify the interface according to the specification of the peripherals themselves.
• Analogue/Digital Interface
To interface two peripherals one of them is digital and the other one is analog we have to add analog to digital converter (ADC) and digital to analog converter (DAC). See figure 2.
