- 1. eZDSP-VC5505 (TMS320C5505)
We are operating the Processor at SysClk of 100Mhz.
We are getting data from Audio Codec AIC3204 at a sampling rate of 48000Hz
The protocol used for interface of TMS320C5505 and AIC3204 is I2S protocol with a BCLK of 1.534MHz.
The data from I2S is transmitted and received to TMS320C5505 using DMA
Our application requires each samples should be passed through a series of “48” FIR filters of order 64.The FIR filtering is done using the DSP LIBRARY function “fir().”The following are the observations and the querries.
Observations:
When the sampling is done at 48000Hz from the codec, the time taken for a block of data to be received from Codec is 20us (approx.)(Wordlength 16)
(BCLK – 1.534MHz.
for 1 bit transmission the time taken from codec is 1/1.534Mhz = 0.6us.
For 32 bits it takes 32/1.534 = 20us apprx)
The cycles taken by fir() API is 414 and the time for one filtering operation is 4.14us (414/100MHz clock).
After 20us of time the block of data from I2S will be refreshed and updated to a new set of samples. Hence the maximum number of FIR filters that be inserted is approximately 5. If I use Ping Pong buffers the maximum number of Fir filters inserted is 10. Our requirement is to implement 48 filters that will be executed within 20us, ie before the next block of sample arrives.
Querries :
(1).How do I implement a series of 48 filters without loss of samples. The entire 48 filters should be executed within 20us , i.e before the next sample arrive ? How can this be done ?
(2). Can TMS320C5505 handle such intensive audio processing in real time. If not kindly suggest some alternative TI processor which we can explore for our audio application.
(3) Is there any way to send data from Processor to the HOST PC through USB interface. We would like to send the processed audio sample data to the HOST PC for our testing purposes. Is it possible ? Is there any other means to send the same.
CODEC AIC3204
Querries:
Is there any way to send only One channel data instead of both the channels. Only one channel data is required to be sent from AIC3204 to TMS320C5505 processor. My requirement is the right channel data should not be sent and whatever samples sent from Codec should be left channel data. Is there any configuration of the codec which requires to be done for enabling this feature ? Is this possible ??
MIC :
Querries:
We interfaces a general collar mic( 2pin) to the Audio IN jack of exDSP VC 5505 USBSTIK. It is not getting recognised. Data is not being read through the mike. Is there any specific MIC type that should be used or there any configuration to be done.
