Embedded System And Real-time Lecture 3

Tishk International University Engineering Faculty Mechatronics Engineering Department Lecture 3: 17/10/2022 Embedded System and Real-time Lecture 3 Instructor: Dr. Rand Basil Alhashimie 1

Outline Multilevel PLA/PAL GAL, CPLD An Embedded System Designer’s View An Embedded System from Customer View An Embedded System from World View 2

MULTI-LEVEL DESIGN USING REGISTERED PAL/PLA 3

Difference between PAL and PLA 4

GENERIC PAL (GAL) 5

GENERIC PAL (GAL) 6

2. COMPLEX PROGRAMMABLE LOGIC DEVICES (CPLDS) SPLDs (PLA, PAL) are limited in size due to the small number of input and output pins and the limited number of product terms Combined number of inputs outputs 32 or so CPLDs contain multiple circuit blocks on a single chip Each block is like a PAL: PAL-like block Connections are provided between PAL-like blocks via an interconnection network that is programmable Each block is connected to an I/O block as well 7

COMPLEX PROGRAMMABLE LOGIC DEVICES (CPLDS) Structure of CPLD 8

COMPLEX PROGRAMMABLE LOGIC DEVICES (CPLDS) Structure of CPLD 9

COMPLEX PROGRAMMABLE LOGIC DEVICES (CPLDS) 10

CPLD Implementation 11

3. Field Programmable Gate Array (FPGA) Field Programmable Gate Array (FPGA) devices were introduced by Xilinx in the mid 1980s. They differ from CPLDs in architecture, storage technology, number of built-in features, and cost, and are aimed at the implementation of high performance, large-size circuits. Field Programmable Gate Arrays (FPGA) can handle larger circuits No AND/OR planes Provide logic blocks, I/O blocks, and interconnection wires and switches 12

PROGRAMMING SPLDS/CPLDS PLAs, PALs, and ROMs are also called SPLDs – Simple Programmable Logic Devices SPLDs must be programmed so that the switches are in the correct places There are two basic types of programming techniques Removable sockets on a PCB In system programming (ISP) on a PCB This approach is not very common for PLAs and PALs but it is quite common for more complex PLDs 13

PROGRAMMING SPLDS/CPLDS Removable sockets on a PCB The SPLD/CPLD is removed from the PCB, placed into the unit and programmed there 14

PROGRAMMING SPLDS/CPLDS In System Programming (ISP) Used when the SPLD/CPLD cannot be removed from the PCB. A special cable and PCB connection are required to program the SPLD from an attached computer. Very common approach to programming more complex PLDs like CPLDs, FPGAs, etc. 15

An Embedded System Design – Designer’s View Measured by: Cost, I/O Connections, Memory size, Function, Performance. 16

An Embedded System Design – Customer’s View Reduced Cost Increased Functionality Improved Performance Increased Overall Dependability 17

An Embedded System Design –World View A complex set of tradeoffs: Optimize for more than just speed Consider more than just the computer Take into account more than just initial product design 18

Embedded System Categories Four General Categories of Embedded Systems General Computing Applications similar to desktop computing, but in an embedded package Video games, set-top boxes, wearable computers, automatic tellers Tablets, Phablets Control Systems Closed loop feedback control of real time system Vehicle engines, chemical processes, nuclear power, flight control 19

Embedded System Categories Signal Processing Computations involving large data streams Radar, Sonar, video compression Communication & Networking Switching and information transmission Telephone system, Internet Wireless everything 20

Next Lecture Real-time System FPGA 21

Embedded System Categories Four General Categories of Embedded Systems General Computing Applications similar to desktop computing, but in an embedded package Video games, set-top boxes, wearable computers, automatic tellers Tablets, Phablets Control Systems Closed loop feedback control of real time system