[Coco] SYSCALL syntax for BASIC09

[Wayne Campbell]

Hi Charlie,

  I have a manual that describes OS9 Syscalls
>   but it does not explain how to use them
>   with Basic09.
>
> 01   PROCEDURE politekey
> 02   TYPE registers=cc,a,b,dp:BYTE;x,y,u:INTEGER
>

This should be a BYTE, not a STRING of 2 characters


> 03???DIM A:STRING[2]
> 04   DIM regs:registers
> 05   PARAM key:STRING[1]

06???A$="0A"
>

This should be the callcode for getting the register packet:
callcode=$8D


> 07   RUN GFX2("CURXY",0,0)
> 08   LOOP
> 09     RUN INKEY(key)
> 10     (* Exit LOOP/ENDLOOP on key press  *)
> 11     EXITIF key<>"" THEN
> 12     ENDEXIT
> 13     (* F$Sleep call - rest of 100ms time slice. )
> 14     regs.x= 1
>

This should be regs.a, containing the path number to use: (0=stdin.
1=stdout, 2=stderrout
regs.a=1

Then regs.b defining the routine to use, these are listed in the OS-9
Manual under Chapter 8: system calls > get status system calls:
 regs.b=2 (filesize routine)

15     RUN syscall(A,regs)
>

RUN syscall(callcode,regs)


> 16     RUN GFX2("CURXY",0,0)
> 17     PRINT " ";
> 18   ENDLOOP
> 19   END
>

Wayne