AppleIIAsm-Collection/disks/disk6_fileio/T.DOSCMD

*
*``````````````````````````````*
* DOSCMD : EXECUTE DOS COMMAND *
*-                            -*
* EXECUTES A DOS COMMAND THAT  *
* IS PASSED VIA AN ASC THAT    *
* FOLLOWS THE JSR TO THE       *
* ROUTINE.                     *
*-                            -*
* CLOBBERS:                    *
*                              *
* FLAGS:  ????----  REG: AXYM  *
*-                            -*
* CYCLES: ???                  *
* SIZE:                        *
*-                            -*
* USAGE:                       *
*                              *
*  JSR DOSCMD                  *
*  ASC "CATALOG"               *
*  HEX 8D00                    *
*-                            -*
* ENTRY                        *
*                              *
* TOP OF STACK                 *
*                              *
* LOW BYTE OF RETURN ADDRESS   *
* HI BYTE OF RETURN ADDRESS    *
*-                            -*
* EXIT                         *
*                              *
* TOP OF STACK                 *
*                              *
* LOW BYTE OF RETURN ADDRESS   *
* HI BYTE OF RETURN ADDRESS    *
*                              *
* .Y = CLOBBERED               *
* .X = UNCHANGED               *
* .A = UNCHANGED               *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
DOSCMD
*
** GET RETURN ADDRESS
*
         PLA
         STA   RETADR
         PLA
         STA   RETADR+1
*
         LDA   #$8D
         JSR   FCOUT
         LDA   #$84       ; CTRL-D
         JSR   FCOUT
*
** NOW SEND STRING TO COUT
*
         LDY   #$01       ; POINT TO NEXT INSTR
:LP
         LDA   (RETADR),Y
         BEQ   :DONE
         JSR   FCOUT
         INY
         BNE   :LP
:DONE
         CLC              ; RESTORE INSTR POINTER
         TYA
         ADC   RETADR
         STA   RETADR
         LDA   RETADR+1
         ADC   #$00
         PHA
         LDA   RETADR
         PHA
*
         RTS
*