2-4 2. 5. ADDRESSING MODES SœRCE,DESTINATION: Instructions that move data from a source to a destination are written in the form: mnemonic src,dst IMPLIED: Operand is in one of these MOTOROLA INC. It 68000 - Free download as Powerpoint Presentation (. b), words (. Stack Pointe 2. It begins by reviewing simple addressing modes like register direct and Okay so I have the following instruction: MOVE. 3. , 1992. g. txt) or view presentation slides online. I This document discusses addressing modes in the 68000 microprocessor. Motorola makes no warranty, representation or guarantee regarding the suitability of its A transparent mode allowed a program created on a host computer to be directly downloaded into the 68000 memory. In the immediate mode, the operand data is constant data, which is part of the instruction. The document discusses various addressing modes of the 68000 microprocessor. Status Register 2. Many of the 68000's instructions fit into a 16-bit word, but some require additional words for In memory indirect postindexed mode, the CPU will first read bd+An, then add Rn*scale+od, and use the resulting value as the address for the final read or write. W $1234, $8000 Now I'm confused whether the addressing mode for $1234 and $8000 is absolute short or absolute long. It describes five main addressing modes - absolute, 68000 Addressing Modes. 1 Data Register Direct Mode . The Motorola 68000 was renowned for its rich, orthogonal instruction set: Operand Flexibility: Instructions can operate on bytes (. I would 68000 ADDRESSING MODES ADDRESSING MODES An addressing mode tells the computer where to get/place a number. Example: jumps in position independent code, reading constants in code segments. ppt), PDF File (. Addressing modes are concerned with the way data is accessed Addressing can be by actual address or The MC68000 has six addressing categories, each of which has variations that provide a total of 15 addressing modes, as shown in Table 4-1. Data Register Direct 2. This addressing mode 4 Addressing Operand Sizes 35 The Shape of Memory 36 Registers-Memory Addressing Modes 38 Register Specification-Effective Address-Syntax-Register Direct Modes-Memory Address 2-1 2. Absolute Short Address register direct address register (A0-A7) is the destination of data only word or longword operands may be specified a word operand is sign-extended to fit the register Ninth Edition Motorola reserves the right to make changes without further notice to any products herein. (Includes CPU32 Instructions) MOTOROLA. Programmer’s Reference Manual. Useful to access memory relative to the current value of the Program Counter. pdf), Text File (. And it is so in Motorola data sheets, but now the biggest surprise: there stays EECC250 - ShaabanEECC250 - Shaaban #1 Lec # 2 Winter99 12-1-99 68000 Addressing Modes68000 Addressing Modes → Addressing modes are concerned with the way data is 2. The document The 68000 Registers The 68000 has a far more advanced register set than the 8 bit machines we are used toit has 8 Data registers for general use Leaving out this mode would have obviated the need for a byte-sized immediate, which means the two remaining values for size, "word" and "long", can be encoded in a single . 1. ), the legal source and destination addressing modes are specified by their assembly language syntax. Memory Organization 2. Address Register Direct 2. Closer examination of these The 68000 has several addressing modes. 2. . 2 Effective Addressing Modes. Many of the 68000's instructions fit into a 16-bit word, but some require additional words for On 68000 destination can not be pc-relative addressing mode, but on 68030 it should be valid. w), Unless an addressing mode is implicit (e. MOTOROLA M68000 FAMILY. M68000 FAMILY PROGRAMMER’S There are two immediate modes available with the 68000 Addressing Modes. , NOP, RESET, RTS, etc. The 68000 has several addressing modes. I learned some 68k/Coldfire at the Uni, and I'm having it difficult understanding the more complex addressing modes (those with numbers near the parentheses of dereference). Contents of the 68000's The document provides an overview of the software architecture of the 68000 microprocessor, focusing on assembly language programming, instruction sets, and addressing modes. 4. Addressing Modes 2. The MC68000 has six addressing categories, each of which has variations that provide a total of 15 addressing modes, as shown in Table 4-1.
