Step by step ...HOW TO CREATE A LIBRARY?

Hi,
thank you for your answer.
I've read this "recipie" before , but i suppose this wom't create a lib.
Am i right?

but i suppose this wom't create a lib
no, but this will

if not exist as.lib goto usliex
del as.lib
:usliex
c:\keil\c51\bin\lib51 c as.lib					>..\trash\trashbin
c:\keil\c51\bin\lib51 a avmain.obj   to as.lib	>..\trash\trashbin

Now you confused me! I am not a C or Compiler expert. I used to write code in assembly all these years.i bet you are right
but a novice like moi....can't handle all this. what i did just now is the following:
i started a new project with my_lib.c file as source with my_func as the fuction that implements the code to be compiled to library and using the #pragma asm i added
assembly code in there , using R7 and R5 to pass variables to asm code.then i configured OUTPUT to create a lib instead of exe and compiled.my_lib was created. can i use this now , or do i have to create a header file?(if yes how????)
Thanks again

PLEASE
rewrite your post - separate and number the questions.

e.g. what does #pragma asm i added have to do with a library?

btw why on earth do you use >#pragma asm instead of just making a .a51 file?

Erik

Hi
I used #pragma asm because i wanted to add my asm routine inside the function that I wrote.
I read some other open source libraries and saw some mixed-langauge implementations of lib-source.
actually i thought that writting a C function with inline assembly and compiling it to Lib is the best way.here is what i did:

#pragma SRC
unsigned char	Dac8801	(unsigned char val,unsigned char chan)
{
if (chan>7) return(0);
#pragma asm
mov	A,R0
push	ACC
mov	A,#0x07
ORL P2,#00000111B
clr	P2.0		;clr	CS
mov	A,R7            ;load dac_no to A
RR	A
RR	A
RR	A
mov		R0,#3
loop1:
RLC	A
MOV P2.2,C
clr	P2.1			;clr	CLK
setb	P2.1		;set	CLK
DJNZ	R0,loop1
mov	A,R5            ;load dac_data to A
mov		R0,#8
loop2:
RLC	A
MOV P2.2,C
clr	P2.1		;clr	CLK
setb	P2.1		;set	CLK
DJNZ	R0,loop2
pop	ACC
mov	R0,A
setb	P2.0
#pragma endasm
return(1);
}

actually i thought that writting a C function with inline assembly and compiling it to Lib is the best way
You can not "compile to lib" you can only "compile to obj" THEN you can put the object in a library.
1) is this a good start?
2) what does it take to make ports and pins be defined outside the library
3) if all is good , how do I write a header file for this?

1) sure, you need code before you can put it in a library; however I still would recommend a pure assembler module.
2) you can't - SFRs are absolute addresses and used at COMPILE time.
3) just as for any other module

Erik

I am afraid i am being a pain in the ...
Anyway you assume that i know how to "write"
a header file , but i don't!
would it be easier if you gave me an example file for lib and header? the features i need is to pass 2 unsigned char to it and control 3 I/O pins inside my function.
my code is in assebly as you already know. i saw a lib that expects a definition of port and pin addresses before including the lib so that the lib "knows" from definition which ports to use. for example a clock pin and a data pin for soft-SPI lib would ask for a definition (inside main source) like:

#define SWSPI_PORT 0x20 // soft-SPI port address
#define CLK 0           //clock pin number
#define SDI 1           // SDI (data) pin number

would it be easier if you gave me an example file for lib and header?
there is tons of examples right here at the Keil site and the below, actually, is an extract from a .h file.

#define SWSPI_PORT 0x20 // soft-SPI port address
#define CLK 0 //clock pin number
#define SDI 1 // SDI (data) pin number

which would tell the compiler that
the library function when refering to
CLK , means P1.0,SDI means P1.1
That works, but require "presence at compile time" which you can not have for a library.

Erik