Specifications

DMA Controller (V40)
Autoinitialize is a feature that automatically reloads the DCU Current
Address and Current Count registers from the Base Address and Base
Count registers, respectively. The reload is done when the Count
register reaches zero. The autoinitialize feature is disabled by
programming AUTI with a logical 0 and enabled with a logical 1.
The ADIR bit defines the operation of the DCU address adjuster. If
ADIR is programmed with a logical 0, the address adjuster increments
the memory address after each data transfer. If ADIR is programmed
with a logical 1, the address is decremented. TMODE defines the
transfer mode to be demand, single, or block. These operating modes
are explained later in this chapter.
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