Data Transfer Types As Programmed In Dcm; Programming Dts And Sts - Motorola MPC8260 PowerQUICC II User Manual

Part IV. Communications Processor Module

18.8.2.2 Data Transfer Types as Programmed in DCM

Table 18-6 summarizes the types of data transfers according to the DCM programming.
Table 18-6. IDMA Channel Data Transfer Operation
S/D FB Read From
01 0 Memory
(STS = SS_MAX)
10 0 Peripheral
(STS = port size or
32)
00 0 Memory
(STS = SS_MAX)
00 0 Memory
(STS = SS_MAX
or less)
01 1 Memory to
peripheral
(DTS = port size or
32)
10 1 Ñ

18.8.2.3 Programming DTS and STS

The options for setting STS and DTS depend on (DCM[DMA_WRAP]) and are described
in the following tables for memory/memory and memory/peripheral transfers.
18-20
Write To
Peripheral Read from memory: Filling internal buffer in one DMA transfer.
(DTS = port size On the bus: one burst or more, depends on STS
or 32)
Write to peripheral: In smaller transfers until internal buffer empties.
On the bus: singles or burst, depends on DTS
Memory Read from peripheral: Filling internal buffer in several DMA
(DTS = transfers.
SS_MAX) On the bus: singles or burst, depends on STS
Write to memory: in one DMA transfer, internal buffer empties.
On the bus: one burst or more, depends on DTS
Memory Read from memory: Filling internal buffer in one DMA transfer.
(DTS = On the bus: one burst or more, depends on STS
SS_MAX or
Write to memory: in one transfer or more until internal buffer
less)
empties.
On the bus: singles or bursts, depends on DTS
Memory Read from memory: Filling internal buffer in one or more DMA
(DTS = transfers.
SS_MAX) On the bus: singles or bursts, depends on STS
Write to memory: in one DMA transfer, internal buffer empties.
On the bus: one burst or more, depends on DTS
Ñ Read transaction from memory while asserting DACK to
peripheral. Peripheral samples the data read from memory.
On the bus: singles or bursts, depends on DTS
Peripheral to Write transaction to memory while asserting DACK to peripheral.
memory Peripheral provides the data that is written to the memory.
(STS = port size On the bus: singles or bursts, depends on STS
or 32)
MPC8260 PowerQUICC II UserÕs Manual
Description (Steady-State Operation)
MOTOROLA