Int 66 Fn 069C  - Digpak - Set Dma Backfill Mode                           [s]

   AX = 069Ch
   DX = mode
       0000h turn backfill mode on
       0001h turn backfill mode off

Return: AX = status
       0000h command ignored
       0001h backfill mode set

See Also: AX=069Dh,AX=069Eh