r8a77850anbg Renesas Electronics Corporation., r8a77850anbg Datasheet - Page 695

• Manufacturer Part Number: r8a77850anbg
• Description: Renesas 32-bit Risc Microcomputer Superh? Risc Engine Family
• Manufacturer: Renesas Electronics Corporation.

This LSI includes an on-chip direct memory access controller (DMAC). Instead of the CPU, the
DMAC can be used to perform data transfers among external devices equipped with DACK
(transfer request acceptance signal), external memory, on-chip memory, memory-mapped external
devices, and on-chip peripheral modules.
14.1
• Number of channels: Twelve channels (channels 0 to 3 can accept an external request)
• Address space: 4 Gbytes on the architecture (Physical address)
• Transfer data length: Byte, word (2 bytes), longword (4 bytes), 16 bytes, and 32 bytes
• Maximum transfer count: 16,777,216
• Address mode: Dual address mode
• Transfer requests:
• Bus mode:
• Priority: Choice of fixed mode and round-robin mode
• Interrupt request: An interrupt request can be generated to the CPU after half of transfers have
• External request detection: Choice of low/high level detection and rising/falling edge detection
• DMA transfer end notification signal: Active levels for DACK can be specified independently
Choice of external request (channels 0 to 3), on-chip peripheral module request, or auto-
request
The following modules can issue an on-chip peripheral module request.
⎯ SCIF0 to SCIF5, HAC0, HAC1, HSPI, SIOF, SSI0, SSI1, FLCTL, and MMCIF
Choice of cycle steal mode (normal mode or intermittent mode) or burst mode
ended, all transfers have ended, or an address error has occurred
of DREQ input
Section 14 Direct Memory Access Controller (DMAC)
Features
14. Direct Memory Access Controller (DMAC)
Rev.1.00 Jan. 10, 2008 Page 665 of 1658
REJ09B0261-0100