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I have the following setup: On the 21065L, the Transmit SPORT 0 is configured for I2S slavemode (external transmit frame syn), with two I2S lines connected to ports 0_A and 0_B, each line carrying a stereo signal (left and right channel). There seems to be no bit in the STCTL0 register or anywhere else, which shows me the current status of the I2S WSpins (left or right), so the question is: when I write a word to the transmit buffer 0_A, how can I determine to which channel (left or right) this word goes to? The paper "Interfacig I2S-compatible audio devices to the ADSP-21065l serial ports" says (on p. 4): " When WS = 0 or low', the data is Channel 1, or Left Channel data in a stereo system. " How can I access the WS status from the 21065Lcore program? Kind regards, Andor Bariska WEISS ENGINEERING LTD. - Professional Digital Audio Products Florastrasse 42 8610 Uster Switzerland phone: +41 1 940 20 06, fax: +41 1 940 22 14 mailto: web: http://www.weiss.ch Maillist:http://groups.yahoo.com/group/weiss-audio |
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I2S question on 21065L
Started by ●October 17, 2002
Reply by ●October 18, 20022002-10-18
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Hi Andor, we have been using the ADSP21065L and ADSP21161N for a few years, the best way to setup the SPORTs is the following: 1. Use DMA with chaining and interrupts with common clock connections in hardware. 2. Initialise the audio system: a. Configure one SPORT receiver for: DSP mode (this transfers 1 word instead of 2 for 1 WS cycle ), no DMA b. Wait for SPORT to receive a sample, do this simply by reading the RX register e.g. r0 = dm(RX0A)* c. Initialise all SPORT registers and kick off the DMA chain. 3. Your SPORT interrupt service routine should only be called by 1 SPORT (RX or TX). * The core may hang while the SPORT waits for WS to transition, but as this is in initialisation, it doesn't matter. We have a system which uses SPORT0/2 in TDM multichannel mode (in and out) and SPORT1/3 carrying 2 I2S inputs and 2 I2S outputs which shows that this approach works. Regards, Alex Young DSP software Engineer Consultant for Philips Digital Systems Laboratories Philips Technology Campus Leuven Interleuvenlaan 74-82 B-3001 LEUVEN, BELGIUM e-mail: Andor Bariska <andor.bariska@w To: "'ADI DSP Support'" <> eiss.ch> cc: "'ADSP eGroup'" <> (bcc: Alex Young/LEU/PDSL/PHILIPS) 17/10/02 17:00 Subject: [adsp] I2S question on 21065L Classification: I have the following setup: On the 21065L, the Transmit SPORT 0 is configured for I2S slavemode (external transmit frame syn), with two I2S lines connected to ports 0_A and 0_B, each line carrying a stereo signal (left and right channel). There seems to be no bit in the STCTL0 register or anywhere else, which shows me the current status of the I2S WSpins (left or right), so the question is: when I write a word to the transmit buffer 0_A, how can I determine to which channel (left or right) this word goes to? The paper "Interfacig I2S-compatible audio devices to the ADSP-21065l serial ports" says (on p. 4): " When WS = 0 or low', the data is Channel 1, or Left Channel data in a stereo system. " How can I access the WS status from the 21065Lcore program? Kind regards, Andor Bariska WEISS ENGINEERING LTD. - Professional Digital Audio Products Florastrasse 42 8610 Uster Switzerland phone: +41 1 940 20 06, fax: +41 1 940 22 14 mailto: web: http://www.weiss.ch Maillist:http://groups.yahoo.com/group/weiss-audio _____________________________________ Note: If you do a simple "reply" with your email client, only the author of this message will receive your answer. You need to do a "reply all" if you want your answer to be distributed to the entire group. _____________________________________ About this discussion group: To Join: Send an email to To Post: Send an email to To Leave: Send an email to Archives: http://groups.yahoo.com/group/adsp Other Groups: http://www.dsprelated.com/groups.php3 ">http://docs.yahoo.com/info/terms/ |
