Third Day Class (Assembler E-learning Cource)

ajaychandra · New User Joined: 31 Mar 2005 Posts: 16 Location: Bangalore

Hi Friends,

By now you should be familiar with the following terms.

Standard Assembler Coding Format
Statement Field, Continuation-Indicator Field and Identification-Sequence Field.
Instruction-Statement Format.

Now Let us start with third lesson?

[b]Assembler Language Structure:[/b]

[b]Overview of Assembler Language Structure (Algorithm):[/b]

1) Source Module is made up of Source Statements, which can be instruction statements or comment statements.
2) Instruction Statements are of three types as Machine Instructions, Assembler Instructions and Macro Instructions. Comment statements can be any characters.
3) All the three instruction statements are composed to form one to four fields as Name, Operation, Operand and Remarks.
4) Operands for a machine instruction are composed of Expressions. Expressions in turn are composed of terms and combination of terms.
5) All together are composed of EBCDIC or DBCS characters

[b]Overview of Machine Instruction Structure (Algorithm):[/b]

1) Name Field: Name field should be a symbol or space. (Can be a ordinary symbol, variable symbol or a sequence symbol)
2) Operation Field: Operation field should be a symbolic operation code. (Includes symbolic macro codes or macro definitions)
3) Operand Field: Operand field can have zero or more arguments.
4) Operand Field: Arguments are composed of expressions.
5) Operand Field: Expressions are composed of terms or arithmetic combination of terms.
6) Operand Field: Terms can be of symbols, location counter reference, symbol arithmetic reference, self defining term or a literals.
7) Operand Field: The self-defining term in turn can be decimal, hexadecimal, binary, character and graphics.

[b]Overview of Assembler Instruction Structure (Algorithm):[/b]

1) Name Field: Name field can be symbol or spaces. (Can be a ordinary symbol, variable symbol or a sequence symbol)
2) Operation Field: Operation field can be of symbolic operation code. (Includes symbolic macro codes or macro definitions)
3) Operand Field: Operand field is the field which can have zero or more operands
4) Operand Field: Operands are composed of data definition instructions and ordinary assembler instructions
5) Operand Field: For data definition (DC and DS instructions) operands can be composed of Duplication factor, Type, Type Extension, Modifiers and Nominal values. Nominal values are of one or more nominal values as decimal number, expression, character string and graphic string.]
6) For all other ordinary instructions operands can be composed of expression, character strings and symbolic options.

[b]Conditional Assembly Instructions Structure (Algorithm):[/b]

1) Name Field: Name field can be of sequence symbols or spaces or variable symbols.
2) Operation Field: Operation field must be a symbolic operation code.
3) Operand Field: Operand field can have zero or more operands
4) Operand Field: Operand are composed of sequence symbols, variable symbols, expressions or expressions sequence symbols.
5) Operand Field: Expressions are the combination of variable symbols and other characters that constitute an arithmetic expression, logical expression or character expression

[b]Machine Instruction Structure (Algorithm):[/b]

1) Name Field: Name field can be a symbol or a character string
2) Name Field: Symbol can be any one of the following three symbols as Ordinary symbols (or spaces), sequence symbols or variable symbols.
3) Name Field: Character string can be of string excluding spaces and commas and string including spaces.
4) Operation Field: Operation field can be of symbolic operation code.
5) Operand Field: Operand field can have zero or more operands
6) Operand Field: Operands can be of one value or sub lists with more than one entry, each entry having a value.
7) Operand Field: Operands are of characters including spaces and commas or excluding spaces.

** Hey Guys try out with each of these algorithms to draw flow chart diagram. **

Topics to learn in next lesson:

[b]Terms, Literals and Expressions [/b]

dabadekiran · New User Joined: 31 May 2005 Posts: 1 Location: hyderbad

good one

RANJINI · New User Joined: 19 Apr 2005 Posts: 11

Hi,
I learnt all the 3 day class. I'm

as I couldn't find any more lessons.

Please start the sessions again.

Thank you,
Ranjini.S

royalchm · New User Joined: 15 Nov 2007 Posts: 29 Location: Bangalore

Its very helpful as a beginner...Please continue the session.......
Thanks,
Hari

enrico-sorichetti · Posted: Mon Dec 31, 2007 5:15 pm

for very good assembler stuff check this link

http://www.bsp-gmbh.com/turnkey/assembler/

Jörgen Engström · New User Joined: 30 Jan 2008 Posts: 3 Location: Sweden

Whoa nice link. Trying, but it is pretty hard to find decent tutorials for beginners in datamanip with mainframe hlasm.

dick scherrer · Posted: Sun Feb 24, 2008 4:32 am

Hello Jörgen and welcome to the forums,

Jörgen Engström · New User Joined: 30 Jan 2008 Posts: 3 Location: Sweden

Thanks dick!

The books you speak of, probably only can find them as e-book or over international sites like amazon. Currently I am documenting the things I learn as a beginner and hopefully be able to put together some documents along the way.

Lucky we got a test-LPAR at work so I can try my code pretty much there, trial and abend!

dick scherrer · Posted: Sun Feb 24, 2008 7:21 am

You're welcome

Yes, i'd check amazon. . .

Even with a test lpar, i'd make sure i was not working in an apf-authorized library. . . .

Good luck and enjoy

Jörgen Engström · New User Joined: 30 Jan 2008 Posts: 3 Location: Sweden

Haha okey. Talked to the most experienced guy there, he set everything up for me and my first question was of course " Can I harm the production system with my assembler trials?" and his response was "No, you'd have to do some strange things to do that".

I will look into apf-authorized library before I get too scared though ^_^ thanks!