Core Configuration
Symphony DSP56724/DSP56725 Multi-Core Audio Processors, Rev. 0
Freescale Semiconductor
5-19
5.6
DMA Request Sources
In previous DSP563xx products, 6 DMA channels were supported. In the DSP56724/DSP56725, the DMA
blocks are updated, and up to 8 DMA channels can be supported.
Additional registers for the additional two DMA channels are included in the DMA modules. In the
DSP56724/DSP56725, each DMA channel receives its own 32 request lines, allowing more flexibility in
the DMA request sources for the different channels, and potentially support for a greater number of DMA
request sources.
Each DMA channel’s Request Source bits (DRS4-DRS0 bits in the DMA Control/Status registers) encode
the source of DMA requests used to trigger the DMA channels’ transfers. The DMA request sources may
be internal peripherals, or external devices requesting service through the IRQA, IRQB, IRQC and IRQD
pins.
The additional registers for the two additional DMA channels are the same as the registers for the other
DMA channels. The previous section shows the addresses of these registers. The DMA status register is
slightly different with 8 channels of DMA:
•
DSTR[6]: DTD6, DMA channel 6 (the seventh channel) transfer has finished.
•
DSTR[7]: DTD7, DMA channel 7 (the eighth channel) transfer has finished.
•
DSTR[10:9]: DCH[2:0]; when DCH[2:0] = 6, it indicates that the active channel is DMA channel
6; when DCH[2:0] = 7, it indicates that the active channel is DMA channel 7.
shows the DMA request sources for all of the 8 DMA channels. All of the 34 DMA request
lines are covered by two request line subsets: one line subset is for DMA channels 0–5, while the other
line subset is for DMA channels 6–7. External request lines are only supported by DMA channel 0–5.
VBA: $C0
to
VBA: $FA
0-2
Reserved
VBA: $FC
0-2
Always-On Interrupt (Always active,
users can mask it or enable it by setting
the corresponding Priority bits in IPRP1
bit 23 and 22.)
VBA: $FE
0-2
EMC/ICC Access Error Interrupt
Table 5-12. DMA Request Sources
Source Select Bits BSR[4:0]
of DMA Channel 0–5
Source Select Bits BSR[4:0]
of DMA Channel 6–7
1
External IRQA
0_0000
No support for these requests.
2
External IRQB
0_0001
3
External IRQC
0_0010
4
External IRQD
0_0011
5
Transfer Done from DMA Channel 0
0_0100
0_0100
Table 5-11. Reset and Interrupt Vector Summary (Continued)
Interrupt Starting Address
Priority Level Range
Description
Notes