HD64F3048VTF8 Datasheet, PDF (249/903 Pages) Renesas Technology Corp – Hardware Manual Renesas 8-Bit Single-Chip

Section 8 DMA Controller
Repeat Mode
One byte or word is transferred per request. A designated number of these transfers are executed.
When the designated number of transfers are completed, the initial address and counter value are
restored and operation continues. No CPU interrupt is requested. One 24-bit address and one 8-bit
address are specified. The transfer direction is determined automatically from the activation
source.
Normal Mode
Auto-request: The DMAC is activated by register setup alone, and continues executing transfers
until the designated number of transfers have been completed. A CPU interrupt can be requested at
completion of the transfers. Both addresses are 24-bit addresses.
• Cycle-steal mode
The bus is released to another bus master after each byte or word is transferred.
• Burst mode
Unless requested by a higher-priority bus master, the bus is not released until the designated
number of transfers have been completed.
External request: One byte or word is transferred per request. A designated number of these
transfers are executed. A CPU interrupt can be requested at completion of the designated number
of transfers. Both addresses are 24-bit addresses.
Block Transfer Mode
One block of a specified size is transferred per request. A designated number of block transfers are
executed. At the end of each block transfer, one address is restored to its initial value. When the
designated number of blocks have been transferred, a CPU interrupt can be requested. Both
addresses are 24-bit addresses.
Rev. 3.00 Sep 27, 2006 page 221 of 872
REJ09B0325-0300