[sdcc-devel] SDCC and reg with asm and RS485 uLan

[Pavel P. <pi...@cm...>]

Hello Sandeep&co,

excuse me for taking your time.
But I have some question and I am offering
RS485 based multi-master protocol.

I first introduce myself:
- I am teaching at Czech Technical University in Prague
- I develop for PiKRON Ltd.
- we use many 51 based boards in some of our instruments 
- we developed some more powerful systems as well
   <http://www.pikron.com/en/main_frame_mo_cpu1.html>
   this board can run uClinux for example or control
   robots
- I have cooperated on BDM debugging for 68376
   <http://cmp.felk.cvut.cz/~pisa/m683xx/bdm_driver.html>
- we have designed uLan communication network for our instruments
   PC side is GNU and some info can be found at
   <http://cmp.felk.cvut.cz/~pisa/ulan/ul_drv.html>
- we provide bigger applications under GNU as well
   <http://www.chromulan.org/>
- it works with ISA and PCI cards and we are preparing 51 based USB
   converter now (code for it will be open)
- I would like to open 51 uLan side to more broad community
   I was able to convert core code from macro assembler into
   SDCC asx8051 syntax, ugh, I need to couple code with C.
   It has been already tested with Keil, but parameters passing is terrible.

What I am dreaming about is possibility to write something like next

inline int uLan_write(char *buf, int len)
{
  unsigned char ll=len, lh=len>>8;
   __asm__(
        "call __uLan_write\n"
     :"r4="(ll),"r5="(lh)
     :"0"(ll) ,"1"(lh),"dptr"(buf) :"memory","r6","r7"
   );
  return ll+lh*0x100;
}

What do you thing about that?
Do you think, that it could be possible with SDCC in future?

Please send copy of reply to my address as well because
I am not regular user of  SDCC but I like it for students
to learn microcontrollers systems. I do not wish them
to end with 10MB of 8051 sources as I have ended.

Best wishes
 
                Pavel Pisa
        e-mail: pi...@cm...
        www:    http://cmp.felk.cvut.cz/~pisa
        work:   http://www.pikron.com