Functional Description
5-32
ADSP-BF537 Blackfin Processor Hardware Reference
a row in its usage of the relevant memory space to allow up to three
pending DMA accesses to issue, plus allowing enough memory
access time for the accesses themselves to complete.
DMA Errors (Aborts)
The DMA controller flags conditions that cause the DMA process to end
abnormally (that is, abort). This functionality is provided as a tool for sys-
tem development and debug, as a way to detect DMA-related
programming errors. DMA errors (aborts) are detected by the DMA chan-
nel module in the cases listed below. When a DMA error occurs, the
channel is immediately stopped (
DMA_RUN
goes to 0) and any prefetched
data is discarded. In addition, a
DMA_ERROR
interrupt is asserted.
There is only one
DMA_ERROR
interrupt for the whole DMA controller,
which is asserted whenever any of the channels has detected an error
condition.
The
DMA_ERROR
interrupt handler must do these things for each channel:
• Read each channel’s
DMAx_IRQ_STATUS
register to look for a channel
with the
DMA_ERR
bit set (bit 1).
• Clear the problem with that channel (for example, fix register
values).
• Clear the
DMA_ERR
bit (write
DMAx_IRQ_STATUS
with bit 1 = 1).
The following error conditions are detected by the DMA hardware and
result in a DMA Abort interrupt.
• The configuration register contains invalid values:
- Incorrect
WDSIZE
value (
WDSIZE = b#11
)
- Bit 15 not set to 0
- Incorrect
FLOW
value (
FLOW = 2
,
3
, or
5
)
-
NDSIZE
value does not agree with
FLOW
.
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...