mod_skel Problem: _mod_skel_function defined two times?

[wackazong]

Since the _mod_skel_function is already defined in the wrapper, shouldn't the following line be taken out of the mod_skel.inc?

;; --------------------------------------------------------------------------
;;  FUNCTION: mod_skel 
;;  DESCRIPTION: mod_skel. does something stupid. Put your code in here instead.
;; 
;;  IN:   -
;;  OUT:  -
;;  USES: - mod_skel_var
;; --------------------------------------------------------------------------


THE NEXT LINE GENERATES A COMPILER ERROR

_mod_skel_function ; (for C)



mod_skel_function
#if _pca9635_def==1	; note this is using the define from the fix in the asm file!
	incf _mod_skel_var, F, BANKED
#endif
	call _mod_skel_extfunc
	return

[audiocommander]

as I understood, the aim of the "mod_skeleton" is to develop modules that can be used within programs.

To develop a program you should use "sdcc_skeleton" where you are free to define every function/variable you like - whereas when you work with mod_skeleton, you should edit the settings to your requirements.

See README.txt in "modules/mod_skel".

best,

Michael

$Id: README.txt 69 2008-02-01 00:20:18Z tk $

Module Skeleton

Your description goes here. As for this skeleton:
Search for "mod_skel" to find stuff you should change when making your module

Files
~~~~~

  mod_skel.inc: can be included into "asm-only" programs (non-relocatable code)
  mod_skel.asm: relocatable wrapper for C based applications
  mod_skel.h:	C headers
  mod_skel.mk:  include this into Makefile to integrate the driver


Integration Hints
~~~~~~~~~~~~~~~~~

C based Applications
~~~~~~~~~~~~~~~~~~~~

  1) Makefile: add "mod_skel.o" to OBJS variable
  
---
# list of objects that should be created and linked
OBJS = mios_wrapper.o mod_skel.o app_lcd.o main.o
---

  2) Makefile: include mod_skel.mk, and enhance mod_skel_DEFINE if required:

---
# include mod_skel driver	; in our example it allows the 'incf' if this is 1, or if you skip this line
mod_skel_DEFINE += -Dmod_skel_def=0

include $(MIOS_PATH)/modules/mod_skel/mod_skel.mk
---

  3) main.c: #include <mod_skel.h>

  4) main.c: add following code to Tick() hook
  
---
  // do the mod_skel thing
  mod_skel_function();
---  

  5) main.c: add code to main.c for functions called by your module:


---
/////////////////////////////////////////////////////////////////////////////
// This function is called by mod_skel
/////////////////////////////////////////////////////////////////////////////
void mod_skel_extfunc(void) __wparam
{
 // Just a dummy empty function
 --mod_skel_var;
}
---

  6) main.c: etc etc etc


  
  
  
"Assembler-Only" Applications
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


  1a) add application specific #defines to the assembly code (e.g. in
      your main.asm file), e.g.:
---	  
#define mod_skel_def=1
---
	  
  1b) main.asm (or main.inc) include the module source: 

---  
#include <mod_skel.inc>
---

  2) Makefile: include mod_skel.mk, and enhance mod_skel_DEFINE if required:

---
# include mod_skel driver	; in our example if this is 1, or by default if you skip this line, it allows the 'incf'
mod_skel_DEFINE += -Dmod_skel_def=0

include $(MIOS_PATH)/modules/mod_skel/mod_skel.mk
---

  3) app_defines.inc: add the variables you can find declared in mod_skel.asm
     Possible Range: 0x10..0x7f
	 Make sure the EQU address is unique in your app!

---
;; for mod_skel module
_mod_skel_var	EQU	0x067
mod_skel_int	EQU	0x068; ..0x69
---

  4) main.asm (or main.inc): add the following code to the USER_Tick function: 
  
---
;; --------------------------------------------------------------------------
;;  This function is called by MIOS in the mainloop when nothing else is to do
;; --------------------------------------------------------------------------
USER_Tick
	call mod_skel_function
	return
---

  
  5) main.asm (or main.inc): add functions which are called from your module:
  
---
;; --------------------------------------------------------------------------
;;  This function is called by mod_skel module
;; --------------------------------------------------------------------------
mod_skel_extfunc
_mod_skel_extfunc
	decf _mod_skel_var, F, BANKED
	return
---

    
  6) main.asm (or main.inc): etc etc etc
  

[TK.]

Have a look into the max72xx driver for a proper implementation example:

http://svnmios.midibox.org/listing.php?repname=svn.mios&path=%2Ftrunk%2Fmodules%2Fmax72xx%2F

the .asm wrapper only contains _<function> labels (these are the labels called by C) when more than a single byte is passed to the function.

If only WREG (or no parameter at all) is passed, the _<function> and <function> is part of the .inc file

Advantage: pure assembly applications without relocatable code only need to include the .inc file

They don't "see" the stuff in .asm and .h

If you consider this, it should be clear which labels should be put into a .inc file, and which additional labels/code/definitions have to be put into an .asm file

Btw.: modules can also be programmed in C only instead of using .asm or .inc

If you find mixed language programming too difficult/confusing, don't hesitate to write a .c module. Your application has very relaxed timing requirements anyhow!

Best Regards, Thorsten.

[wackazong]

I need some low level routines for blinking the LEDs, thats why I turned to assembler.

@audiocommander: Thats what I did actually, I have a sdcc skeleton which relies on a mod_skel module for the low level routines driving the PCA9635 LED driver. I thought this would be the best way to implement it in a way that maybe also other people can use the PCA9635 driver.

The whole thing compiles and works, but only if I take the mentioned line out of the code. I was just wondering about the double definition of the _<function> label, but now by what TK said its clear:

1) if the function passes only WREG, or no parameter, the label is in the mod_skel.inc. Logically it would make more sense to me to also put that in the wrapper, but by putting it in the .inc you can save one rgoto

2) if not, the label (and the wrapper code) is in the mod_skel.asm

Thanks and best, ALEXander.

[stryd_one]

The whole thing compiles and works, but only if I take the mentioned line out of the code.

Compiles fine here... Must've been something you modified. If you paste the error and your code I'll show you just what causes it.