******************
* GFXE Test Harness
* Provides hookup to Test Video Device Driver
*  for GFXE testing instead of using KBVDIO direct
******************

      leax vpath,pcr     open path to development
      lda #2             device driver
      os9 i$open         
      lbcs error
      sta stdout,s       make this stdout
      ldu basret,s       fetch return address
*N.B. Assumes U Reg **NOT** destroyed by GFXE!!
      leax vcls,pcr      patch in new return addr
      stx basret,s       code will return here
      bra vend

vcls  leas -2,s          restore original RTS addr
      leas -datsiz,s     setup stack frame again
      stb match,s        any error code
      stu basret,s       restore proper address
      lda stdout,s
      os9 i$close        close the path
      ldb match,s        original error
      leas datsiz,s      put back stack
      lbne error         return error code
      rts                finish here
vpath fcs ./VID1.
vend  

** end of test harness

