DMA Operating Modes: Transfer Types
MSC8113 Reference Manual, Rev. 0
Freescale Semiconductor
16-9
consecutive channels. The even channel performs the read (from requestor/memory into
the DMA FIFO), and the odd channel performs the write (DMA FIFO to the other
memory/requestor).
Flyby or single access transaction. In Flyby mode, the data path is between a peripheral
and memory with the same port size, located on the same bus. Flyby operations do not
require access to the DMA FIFO:
— A read from peripheral is a write transaction to memory.
— A write to peripheral is a read transaction from memory.
The advantage of a flyby transaction is that the data is transferred in a single cycle and not
in two, as in a normal transaction. When the transaction source drives data on the bus, the
transaction destination samples it. Flyby transactions occur between external peripherals
and external memories on the system bus. They also occur between internal memories and
internal memories (M1 of one SC140 core to M1 of another SC140 core, M2 to M1, M1 to
M2). When a flyby transaction between two internal memories is requested, one of the M1
memories operates as a peripheral. This memory ignores the address phase. It has an
associated flyby counter, which receives a
DACK
signal from the DMA controller. The
flyby counter should be programmed with the initial M1 memory address. When the
counter receives the asserted
DACK
qualified with
PSDVAL
, it replaces the local bus address
to the M1 memory by its own value. The other memory operates as a “normal” memory
responding to the address phase. To change the flyby counter A value, program the FlyBy
Address Control Registers (FLBACRA) in the EQBS with the M1 memory address
(according to the local bus address space). The address should be divided by 8 and written
to the FlyBy Start Address, FLBSA in the FlyBy Address Control Register. Same
procedure can be done also on FlyBy Address Control Register B (FLBACRB). These two
Flyby Address counters can work in parallel. See the FLBSA, FLBSB description in
Section 9.3.9, EQBS Programming Model.
Note:
When programming the DMA controller for a flyby transaction between two on-device
memories, use the
DRACK
protocol for higher performance. See Section 16.1, DMA
Note:
DMA channels are coupled in pairs (0 and 1, 2 and 3, up to 14 and 15). Do not use two
coupled channels simultanously for flyby or single access transactions.
Summary of Contents for MSC8113
Page 1: ...MSC8113 Reference Manual Tri Core 16 Bit Digital Signal Processor MSC8113RM Rev 0 May 2008 ...
Page 20: ...MSC8113 Reference Manual Rev 0 xx Freescale Semiconductor Contents ...
Page 28: ...MSC8113 Reference Manual Rev 0 xxviii Freescale Semiconductor ...
Page 56: ...MSC8113 Reference Manual Rev 0 1 28 Freescale Semiconductor MSC8113 Overview ...
Page 76: ...MSC8113 Reference Manual Rev 0 2 20 Freescale Semiconductor SC140 Core Overview ...
Page 134: ...MSC8113 Reference Manual Rev 0 4 30 Freescale Semiconductor System Interface Unit SIU ...
Page 168: ...MSC8113 Reference Manual Rev 0 6 18 Freescale Semiconductor Boot Program ...
Page 180: ...MSC8113 Reference Manual Rev 0 7 12 Freescale Semiconductor Clocks ...
Page 260: ...MSC8113 Reference Manual Rev 0 8 80 Freescale Semiconductor Memory Map ...
Page 300: ...MSC8113 Reference Manual Rev 0 9 40 Freescale Semiconductor Extended Core ...
Page 304: ...MSC8113 Reference Manual Rev 0 10 4 Freescale Semiconductor MQBus and M2 Memory ...
Page 308: ...MSC8113 Reference Manual Rev 0 11 4 Freescale Semiconductor SQBus ...
Page 590: ...MSC8113 Reference Manual Rev 0 17 46 Freescale Semiconductor Interrupt Processing ...
Page 614: ...MSC8113 Reference Manual Rev 0 18 24 Freescale Semiconductor Debugging ...
Page 622: ...MSC8113 Reference Manual Rev 0 19 8 Freescale Semiconductor Internal Peripheral Bus IPBus ...
Page 724: ...MSC8113 Reference Manual Rev 0 21 32 Freescale Semiconductor UART ...
Page 920: ...MSC8113 Reference Manual Rev 0 25 150 Freescale Semiconductor Ethernet Controller ...
Page 1171: ...MSC8113 Reference Manual Rev 0 Freescale Semiconductor C 61 EF wait_rts P 01077FFC 9F rts 71 ...
Page 1172: ...MSC8113 Reference Manual Rev 0 C 62 Freescale Semiconductor MSC8113 Boot Code ...
Page 1202: ...MSC8113 Reference Manual Rev 0 Index 30 Freescale Semiconductor Index ...