view level1/modules/dwwrmess.asm @ 3036:42861a1dd59e

Low level driver update to CoCoSDC provided by Darren.
author David Ladd <drencor-xeen@users.sf.net>
date Fri, 09 Jan 2015 12:32:56 -0600
parents c92a6c65bbd9
children c505ae3120c4
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*******************************************************
*
* DWWriteMESS
*  
*  4/27/10 AAW - Based on John Linville's example
*
* Entry:
*    X  = starting address of data to send
*    Y  = number of bytes to send
*
* Exit:
*    X  = address of last byte sent + 1
*    Y  = 0
*    All others preserved
*


DWWrite   pshs      u,d,cc              ; preserve registers
          orcc      #$50                ; mask interrupts

txByte   ldb       ,x+                 ; get a byte to transmit
         stb       $ffe0               ; write it to the FIFO
         leay      ,-y                ; decrement byte counter
         bne       txByte              ; loop if more to send          
          
          puls      cc,d,u,pc           ; restore registers and return