10.6.1 Program Control Instructions These instructions include branches, jumps, and subroutine calls as listed in Table 10.11. Consider Bee d. There are 14 branch conditions. This means that the cc in Bee can be replaced by 14 conditions providing 14 instructions: BCC, BCS, BEQ, BGE, BGT, BHI, BLE, BLS, BLT, BMI, BNE, BPL, BVC, and […]
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Posts by Farahat
Logical instructions , shift and rotate instructions , bit manipulation instructions and binary-coded-decimal instructions
10.6.1 Logical Instructions These instructions include logical OR, EOR, AND, and NOT as shown in Table 10.7. • Consider AND. B # $8 F, DO . If prior to execution of this instruction, [DO.B] = $72, then after execution of AND. B # $ 8 F, D0, the following result is obtained: Z = 0 […]
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68000 Delay Routine
10.7 68000 Delay Routine Typical 68000 software delay l00ps can be written using MOVE and DBF instructions. For example, the following instruction sequence can be used for a delay l00p of 2 millisecond: Note that DBF.W in the above decrements D0 .W by one, and if DO.W "’ -1 branches to DELAY; ifDO.W = -1, […]
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Example on 68000 programming part 1
Example 10.1 Determine the effect of each of the following 68000 instructions: CLR D0 MOVE. L D1, D0 CLR.L (A0) + MOVE -(A0), D0 MOVE 20 (A0 ), D0 MOVEQ.L #$D7, D0 MOVE 21 (A0, Al.L), D0 Assume the following initial configuration before each instruction is executed; also assume all numbers in hex: Example 10.2 […]
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Example on 68000 programming
Example 10.8 Write a 68000 assembly language program that will perform : 5 x X+ 6 x Y + [Y/8] [ D l.L] where X is an unsigned 8-bit number stored in the lowest byte of D0 and Y is a 16-bit signed number stored in the upper 16 bits of D I.Neglect the remainder […]
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Functional categories of 68000 addressing modes , 68000 instruction set , data movement instructions , exg and swap instructions , lea and pea instructions , link and unlk instructions , arithmetic instructions , addition and subtraction instructions , multiplication and division instructions , compare, clear, and negate instructions , test instruction , test and set instruction .
10.5 Functional Categories Of 68000 Addressing Modes All of the 68000 addressing modes in Table 10.2 can be further divided into four functional categories as shown in Table 10.3. • Data Addressing Mode. An addressing mode is said to be a data addressing mode if it references data objects. For example, all 68000 addressing modes […]
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Motorola mc68000 : introduction , 68000 registers , 68000 memory addressing , 68000 addressing modes , register direct addressing , address register indirect addressing , absolute addressing , program counter relative addressing , immediate data addressing and implied addressing .
MOTOROLA MC68000 This chapter describes the basic features of Motorola’s MC68000 (16-bit microprocessor). The addressing modes, instruction set, I/O, and system design concepts of the MC68000 are covered in detail. Motorola’s original MC68000 was designed using HMOS technology. Motorola’s MC68000 is replaced it by a lower power MC68HC000, which is designed using HCMOS technology. The […]
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Questions and problems
QUESTIONS AND PROBLEMS 9.1 What is the basic difference between the 8086, 8086-1, 8086-2, and 8086-4? 9.2 Assume (DS)=1000H, (SS)=2000H, (CS)=3000H, (BP)=OOOFH, (BX)=000AH before execution of the following 8086 instructions: (a) MOV CX,[BX] (b) MOV DX,[BP] Which instruction will be executed faster by the 8086, and why ? 9.3 What is the purpose of the […]
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8086 I/O Ports , Important Points To Be Considered for 8086 Interface to Memory and I/O and 8086-Based Microcomputer
9.9.3 8086 I/O Ports Devices with 8-bit I/O ports can be connected to either the upper or the lower half of the data bus. If the I/O port chip is connected to the lower half of the 8086 data lines (AD0- AD7), the port addresses will be even (A0 = 0). On the other hand, […]
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Interfacing an 8086-Based Microcomputer to a Hexadecimal Keyboard and Seven-Segment Displays , Basics of Keyboard and Display Interface to a Microcomputer and Hex Keyboard Interface to an 8086-Based Microcomputer
9.12 Interfacing an 8086-Based Microcomputer to a Hexadecimal Keyboard and Seven-Segment Displays This section describes the characteristics of the 8086-based microcomputer used with a hexadecimal keyboard and a seven-segment display. 9.12.1 Basics of Keyboard and Display Interface to a Microcomputer A common method of entering programs into a microcomputer is via a keyboard. A popular […]
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