NT1110 Computer Structure and Logic Unit 6 (Module 4A) MEMORY, STORAGE, AND NUMBERING SYSTEM 1

Class Agenda 7/22/16 Chapter 2, 6 and 8 Learning Objectives Discussion on Assignments and Lab. Break Times as per School Regulations. Class Quiz 2 Assignment will be given in the next class Reading Assignment.

Objectives Convert numbers between binary, decimal, and hexadecimal number system. Explain how a computer manages information using various memory and storage devices.

Topics Numbering Systems Used in Computers Basic Boolean Operations Random Access Memory (RAM) Dual Inline Memory Module (DIMM) and Direct Rambus Memory (RDRAM) Modules Installation

Hardware Needs Software to Work Computer’s physical components Monitor, keyboard, memory, hard drive Software Instruction set Directs hardware to accomplish a task Uses hardware for four basic functions Input, processing, storage, output Hardware components Require an electrical system

Figure 1-1 Computer activity consists of input, processing, storage, and output Courtesy: Course Technology/Cengage Learning

Hardware Needs Software to Work (cont’d.) User interaction with computer User and software communicate with input device Hardware uses two states: on and off Figure 1-2 All communication, storage, and processing of data inside a computer are in binary form until presented as output to the user Courtesy: Course Technology/Cengage Learning

Introducing Data and Information, Bits and Bytes Computers use binary digits (bits) to record information electronically Bits represent either value of 0 or 1 Bit is smallest unit of data computers work with Computers work with multi-digit binary numbers Nibble Byte Word Doubleword 8

Nibble, Byte, Word, Double Word 9 Figure 1-2

Kilobyte, Megabyte, Gigabyte, Terabyte Term Size (Bytes) Size (2N Bytes) Rounded by Size (Bytes) Kilobyte 1024 210 1,000 Megabyte 1,048,576 220 1,000,000 Gigabyte 1,073,741,824 230 1,000,000,000 Terabyte 1,099,511,627,776 240 1,000,000,000,000 Kilobyte, Megabyte, Gigabyte, Terabyte 10 Table 1-1

Binary Representation Figure 1-3 All letters and numbers are stored in a computer as a series of bits, each represented in the computer as on or off Courtesy: Course Technology/Cengage Learning

Boolean Operations Boolean Operations is a mathematical system for the manipulation of variables that can have one of two values. In formal logic, these values are “true” and “false.” In digital systems, these values are “on” and “off,” 1 and 0, or “high” and “low.” Boolean expressions are created by performing operations on Boolean variables. Common Boolean operators include AND, OR, and NOT.

Boolean Operations A Boolean operator can be completely described using a truth table. The truth table for the Boolean operators AND and OR are shown at the right. The AND operator is also known as a Boolean product. The OR operator is the Boolean sum.

Boolean Operations The truth table for the Boolean NOT operator is shown at the right. The NOT operation is most often designated by an overbar. It is sometimes indicated by a prime mark ( ‘ ) or an “elbow” ().

Converting Binary 01111011 to Decimal 123 Multiply the decimal digit value times the binary value in each of the eight columns. Add the eight numbers found from the previous step (bottom row in the table). Converting Binary 01111011 to Decimal 123 Figure 1-7

Storage Devices Primary storage (main memory) Temporary storage used by the processor Secondary storage (permanent storage) Enables data to persist after machine turned off Examples: hard drive, CD, DVD, USB drive Primary-secondary memory relationship analogy Library book stacks: permanent storage Books moved to a desk: temporary storage

Figure 1-12 Memory is a temporary place to hold instructions and data while the CPU processes both Courtesy: Course Technology/Cengage Learning

Primary Storage Provided by random access memory (RAM) RAM chips Located on motherboard, adapter cards RAM chips Embedded on small board Plugs into motherboard Most common: dual inline memory module (DIMM) Video memory: embedded on video card Volatile memory Non-volatile memory

Figure 1-13 A DIMM holds RAM and is mounted directly on a motherboard Courtesy: Course Technology/Cengage Learning

Memory Hierarchy

Memory Hierarchy 2 Memory issues Faster access time grater cost per bit Greater Capacity Smaller cost per bit Greater capacity slower access speed Going down Memory Hierarchy Decreasing cost per bit Increasing capacity Increasing access time Decreasing frequency of access to the memory by the processor

Memory Address Numbers assigned to physical memory location either on RAM or ROM Software can only access data on memory by using their address Memory addresses are communicated on the address bus The number is made when OS first loads

Memory Address2

Primary Storage RAM (random access memory): Device providing temporary storage Located on motherboard and on other circuit boards Three types of RAM boards (memory modules): DIMM (dual inline memory module) RIMM (Rambus inline memory module) SIMM (single inline memory module) RAM is volatile (data does not persist) ROM (read-only memory) is nonvolatile

Memory Technologies Random access memory (RAM) Holds data and instructions used by CPU Static RAM (SRAM) and dynamic RAM (DRAM) Both volatile memory Figure 5-34 RAM on motherboards today is stored in DIMMs

Memory Technologies Variations of DRAM DIMM – dual inline memory module small outline DIMM (SO-DIMM) – used on laptops microDIMMs – used on subnotebook computers RIMM and SIMM (outdated) Differences among DIMM, RIMM, SIMM modules Data path width each module accommodates How data moves from system bus to module

Table 4-3 Types of memory modules

Table 4-3 Types of memory modules (continued)

DIMM Technologies DIMM (dual inline memory module) 64-bit data path Independent pins on opposite sides of module Older DIMMs Asynchronous with system bus Synchronous DRAM (SDRAM) Runs synchronously with system bus Two notches Uses 168 pins

DIMM Technologies Double Data Rate SDRAM Also called DDR SDRAM, SDRAM II, DDR Two times faster than SDRAM DDR2 SDRAM Faster than DDR and uses less power DDR3 SDRAM Faster than DDR2 and uses less power DDR2 and DDR3 Use 240 pins Not compatible: use different notches

RIMM Technologies Direct Rambus DRAM C-RIMM (Continuity RIMM) Also known as RDRAM, Direct RDRAM, Rambus RIMM memory module Expensive and slower than current DIMMs RIMMs using 16-bit data bus: two notches, 184 pins RIMMs using 32-bit data bus: single notch, 232 pins C-RIMM (Continuity RIMM) Placeholder module Ensures continuity throughout all slots No memory chip

How to Upgrade Memory Basic technique Problems solved Add more RAM modules Problems solved Slow performance Applications refusing to load An unstable system Windows “Insufficient memory” error message

How to Upgrade Memory Questions to ask How much RAM do I need and how much is currently installed? How many and what kind of memory modules are currently installed on my motherboard? How many and what kind of modules can I fit on my motherboard? How do I select and purchase the right modules for my upgrade? How do I physically install the new modules?

How Do I Select and Purchase the Right Memory Modules? Using a web site to research your purchase Look for search utility matching modules to board Figure 5-56 The Kingston web site DIMM recommendations for a particular motherboard

How Do I Install the New Modules? Precautions: Always use a ground bracelet Turn off power, unplug power cord, press power button, remove case cover Handle memory modules with care Do not touch metal contacts on memory module or expansion cards Do not stack cards or modules Look for notches on one side or in the middle for correct orientation

How Do I Install the New Modules? Installing DIMMS Pull out supporting arms on the sides of the slot Use notches on DIMM edge connector as a guide Insert DIMM straight down into the slot Ensure supporting arms lock into position New installations are generally uncomplicated Usually involve placing memory on motherboard Older computers may need change to CMOS setup If new memory not recognized try reseating device

Unit 6 Lab Identifying and Installing RAM in a PC Converting Numbers to Various Numbering Systems.”

Reading Assignment. Reading: Computer Structure and Logic, Chapter 2, pp. 35–52; Chapter 6, pp. 195–228; and Chapter 8, pp. 304–305.