About the course
Downloads
Introduction to DSM51ASS
Exercises
Equipment:
System Design Kit DSM51
Software:
References:
Information for sympathizer with the course:
dsm51ass.zip
- 8051 Assembler and documentation.
80c51.zip
- Hardware Documentation of 80C51.
- DSM-51.zip
- DSM-51.exe 3.02 (Windows) package used to run programs on the DSM-51 training kit is also available at the manufacturer's website.
A typical line of the program is as follows:
<symbol> <instruction> [<operand>] [;<comment>]
Each pair of fields in a program line must be separated with at least one character spaces (or tabs). Field labels may be empty but must occur, which means that you can not start writing the command mnemonics from the beginning of the line, it must be preceded by at least one space of the individual fields is as follows:
Example (a few instructions, without the sense).
To ensure that the Cross Assembler can distinguish between a symbol and a number, all symbols must start with either a letter or an underscore '_' and can contain any combination of letters, digits and underscores. Symbols can be defined only once. The following are examples of legal symbols:
PI
Serial_Port_Buffer
LOC_4096
Labels are special cases of symbols. Labels are used only before statements that have
physical addresses associated with them. Examples of such statements are assembly
language instructions, data storage directives (DB and DW), and data reservation
directives (DS and DBIT). Labels must follow all the rules of symbol creation with the
additional requirement that they be followed by a colon. The following are legal examples
of label uses:
TABLE_OF_CONTROL_CONSTANTS:
DB 0,1,2,3,4,5 (Data storage)
MESSAGE: DB 'HELP' (Data storage)
VARIABLES: DS 10 (Data reservation)
BIT_VARIABLES: DBIT 16 (Data reservation)
START: MOV A,#23 (Assembly language instruction)
;10ms = 36*256 cykli
;Mod 1 - przestawiam tylko starszy bajt
TMOD_SET EQU 00010000B
TH0_SET EQU 256-30
TH1_SET EQU 256-36
IE_SET EQU 10001010B ;przerwania T0 i T1
IP_SET EQU 00001000B ;wyższy priorytet T1
MOV DISPLAY+4,#0
INC DISPLAY+5
MOV A,#6
CJNE A,DISPLAY+5,INTT1_END
MOV DISPLAY+5,#0
INTT1_END:
POP PSW
POP ACC
To execute the program, it must be assembled, that menas translated into machine language. For this, the assembler DSM51ASS is usefull. Invoke it from the command line system
DSM51ASS <name>
<name> path to the file containing the program.
Assembler creates two files:
<name>. hex - contains the object code in Intel HEX format
<name>. lst - Program listing
Exercise 1a
