Symphony DSP56724/DSP56725 Multi-Core Audio Processors, Rev. 0
19-20
Freescale Semiconductor
Asynchronous Sample Rate Converter
7
FPWT
FP is in wait state
This bit is for debug only.
1 Indicates that filter processor is in wait states.
0 Indicates that filter processor is not in wait states.
If ASRCTR:AFPWE=1 and ASRCTR:ASDBG=1, an interrupt will be proposed when this bit is set.
6
AOLE
Overload Error Flag
1 Indicates that the task rate is too high for the ASRC to handle.
The reasons for overload may be:
• too high input clock frequency
• too high output clock frequency
• incorrect selection of the pre-filter
• low DSP system clock
• too many channels
• underrun
• or any combination of the reasons above.
Since the ASRC uses the same hardware resources to perform various tasks, the real reason for the
overload is not straightforward, and it should be carefully analyzed by the programmer.
If ASRCTR:AOLIE=1, an interrupt will be proposed when this bit is set.
With this bit set = 1, writing any value into the status register will clear this bit and can clear the
interrupt request proposed by this bit.
5
AODFC
Number of data in Output Data Buffer C is greater than threshold
1 Indicates that the number of data words already existing in ASRDORC is greater than the
threshold, and the DSP can read data from ASRDORC. When AODFC is set, the ASRC generates
a data output C interrupt request to the DSP core, if enabled (that is, ASRCTR:ADOEC = 1).
A DMA request is always generated when the AODFC bit is set, but a DMA transfer takes place only
if a DMA channel is active and triggered by this event.
4
AODFB
Number of data in Output Data Buffer B is greater than threshold
1 Indicates that the number of data words already existing in ASRDORB is greater than the
threshold, and the DSP can read data from ASRDORB. When AODFB is set, the ASRC generates
a data output B interrupt request to the DSP core, if enabled (that is, ASRCTR:ADOEB = 1).
A DMA request is always generated when the AODFB bit is set, but a DMA transfer takes place only
if a DMA channel is active and triggered by this event.
3
AODFA
Number of data in Output Data Buffer A is greater than threshold
1 Indicates that the number of data words already existing in ASRDORA is greater than the
threshold, and the DSP can read data from ASRDORA. When AODFA is set, the ASRC generates
a data output A interrupt request to the DSP core, if enabled (that is, ASRCTR:ADOEA = 1).
A DMA request is always generated when the AODFA bit is set, but a DMA transfer takes place only
if a DMA channel is active and triggered by this event.
2
AIDEC
Number of data in Input Data Buffer C is less than threshold
1 Indicates that the number of data words still available in ASRDIRC is less than the threshold, and
the DSP can write data to ASRDIRC. When AIDEC is set, the ASRC generates a data input C
interrupt request to the DSP core, if enabled (that is, ASRCTR:ADIEC = 1).
A DMA request is always generated when the AIDEC bit is set, but a DMA transfer takes place only
if a DMA channel is active and triggered by this event.
Table 19-12. Status Register (ASRSTR) (Continued)
Bit
Field
Description