DMA Controller
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Peripherals
12.3.1.1 TMS320C30 and TMS320C31 DMA Controller
The ’C30 and ’C31 have an on-chip direct memory access (DMA) controller
that reduces the need for the CPU to perform input/output functions. The DMA
controller can perform input/output operations without interfering with the
operation of the CPU. Therefore, it is possible to interface the ’C30 and ’C31
to slow external memories and peripherals (A/Ds, serial ports, etc.) without
reducing the computational throughput of the CPU. The result is improved sys-
tem performance and decreased system cost.
12.3.1.2 TMS320C32 Two-Channel DMA Controller
The ’C32 has an improved DMA that supports two channels and configurable
priorities. The next sections discuss the new features.
The ’C32 has a two-channel (channel 0 and channel 1) DMA instead of a one-
channel DMA as in the ’C30/’C31 devices. The ’C32’s DMA functions similarly
to that of the ’C30/’C31 DMA but with the addition of DMA/CPU priority scheme
and inter-DMA priority mode. Although the ’C32 CPU supports both floating-
point and integer data access with different data size from the external
memory, the ’C32’s DMA transfer is strictly an integer data transfe r. T he int eger
data access of the ’C32 DMA is the same as the CPU integer d at a acc es s —
32-bit internal and data size conversion at the external memory interface port.