List File Formats

808O/808S Assembler

Assembly Output Line

ColumnsDeSCription

1Assembler error code. If the assembler encountered a syntax error in this source line, the appropriate error code appears in this column. Otherwise, this column is blank. If an error occurs in the present line, the following line will be blank except for a decimal sequence number in columns 3-6en- closed by parentheses. This sequence number is a pOinter to the previous line containing an error. The first error encountered in a program will be fol- lowed by a line with a pOinter equal to zero. See Chapter 7 for error codes.

2Minus sign (-) indicates macro definition; otherwise blank.

3-6The address assigned to the first byte of the object code shown in columns 8-9of thi~ line is printed in hexadecimal. In addition, the result of the value- generating assembler directives ORG, EQU, SET, and END will appear in this field. For END, the program start address value will appear in this field if specified; otherwise blank.

7Blank.

8-9The first byte of object code produced by the assembler for this source line is printed here in hexadecimal. If the source statement produces no object code (comments and assembler directives), this field is blank.

10-11 Second byte of object code in hexadecimal. This field will be blank if the source statement generates only one byte of object code or no object code.

12-13 Third byte of object code in hexadecimal, if generated; otherwise, blank.

14-15 Fourth byte of object code in hexadecimal, if generated; otherwise, blank.

16Blank.

17Object code type. The relocatability of an operand is determined by the segment in which the operand lies, not by the segment that references the operand. Values are as follows:

C = CODE

- segment relocatable

o = DATA

- segment relocatable

S = STACK

- segment relocatable

M= MEMORY - segment relocatable

E = EXTERNAL

For a discussion of relocatability, see the 8080/8085 Assembly Language

Programming Manual.

18Blank if no nested source INCLUDE files; otherwise, the number 1-4 indicating the level of nesting.

19Blank if not listing a source INCLUDE file; otherwise an "=" sign.

20-23 Four character positions containing the source line number in decimal, right-justified and left blank-filled.

24Macro expansion flag. A "+ II in this column indicates that the source line was produced as a result of a macro expansion. Otherwise, this column will be blank.

25-...

Listing of assembler source text. This field terminates at column 72 for most

 

output devices other than the line printer. For a line printer, this field ter-

 

minates at column 132.

For DB and DW assembler directives containing a list of operands, the generated code for each operand is listed on a separate line.

If a list line exceeds the specified page width, the source line continues starting at column 2S of the next line.

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Intel 8085, 8080 manual List File Formats 808O/808S Assembler Assembly Output Line

8080, 8085 specifications

The Intel 8085 and 8080 microprocessors were groundbreaking innovations in the world of computing, paving the way for future microprocessor development and personal computing.

The Intel 8080, introduced in 1974, was an 8-bit microprocessor that played a fundamental role in the early days of personal computing. With a 16-bit address bus, it had the capability to address 64 KB of memory. Running at clock speeds of 2 MHz, the 8080 was notable for its instruction set, which included 78 instructions and 246 opcodes. It supported a range of addressing modes including direct, indirect, and register addressing. The 8080 was compatible with a variety of peripherals and played a crucial role in the development of many early computers.

The microprocessor's architecture was based on a simple and efficient design, making it accessible for hobbyists and engineers alike. It included an 8-bit accumulator, which allowed for data manipulation and storage during processing. Additionally, the 8080 featured registers like the program counter and stack pointer, which facilitated program flow control and data management. Its ability to handle interrupts also made it suitable for multitasking applications.

The Intel 8085, introduced in 1976, was an enhancement of the 8080 microprocessor. It maintained a similar architecture but included several key improvements. Notably, the 8085 had a built-in clock oscillator, simplifying system design by eliminating the need for external clock circuitry. It also featured a 5-bit control signal for status line management, which allowed for more flexible interfacing with peripheral devices. The 8085 was capable of running at speeds of up to 3 MHz and had an extended instruction set with 74 instructions.

One of the standout features of the 8085 was its support for 5 extra instructions for stack manipulation and I/O operations, which optimized the programming process. Additionally, it supported serial communication, making it suitable for interfacing with external devices. Its 16-bit address bus retained the 64 KB memory addressing capability of its predecessor.

Both the 8080 and 8085 microprocessors laid the groundwork for more advanced microprocessors in the years that followed. They demonstrated the potential of integrated circuits in computing and influenced the design and architecture of subsequent Intel microprocessors. Their legacy endures in the way they revolutionized computing, making technology accessible to a broader audience, and their influence is still felt in the design and architecture of modern microprocessors today.