Thanks for your reply. In fact, I have tried to write the driver by using WavePCI, but the IC manufacturer suggested us to use WaveCyclic instead of WavePCI. I am very happy to hear you getting WaveCyclic works. If it's possiblem, can you just let me know the setting of Master Channel? or just please give us only the part of DMA channel source code for reference? This is really thanks. Regards, Peter ----- Original Message ----- From: Sam Tertzakian To: wdmaudiodev@xxxxxxxxxxxxx Sent: Thursday, June 23, 2005 3:58 AM Subject: [wdmaudiodev] Re: Problem on setting wavecyclc I struggled for a long time with WaveCyclic model. I finally got it work, but I can tell you this.even if you get it to work, you will have other problems. You should not use WaveCyclic. Use WavePCI instead. (Don't let the "pci" bother you.you can use it for any kind of driver). You will be a lot happier. ------------------------------------------------------------------------------ From: wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of PB Sent: Sunday, June 19, 2005 9:19 AM To: wdmaudiodev@xxxxxxxxxxxxx Subject: [wdmaudiodev] Problem on setting wavecyclc I am writing an window audio driver by Microsoft Window Driver Development Kit(DDK) for window XP. I have followed the archecture of the driver sample code provided under the folder SB16 which are using WaveCyclic Interface and Slave Channel method to build the sound card audio driver. However, since our chip on the sound card have not provide us the default channel, we use the Master Channel method to create DMA channel and using allocate buffer API similar as Slave method provided in the sample code. ------------------------------------------------------------ e.g. ntStatus = Port->NewMasterDmaChannel ( &MyDmaChannel, // OutDmaChannel NULL, // OuterUnknown (opt) NULL, // ResourceList (opt) MAXLEN_DMA_BUFFER, //Maximum Length TRUE, // Dma32BitAddresses FALSE, // Dma64BitAddresses Width32Bits, // DmaWidth Compatible ); // DmaPort if (NT_SUCCESS(ntStatus)) { ULONG lDMABufferLength = MAXLEN_DMA_BUFFER; do { ntStatus = MyDmaChannel->AllocateBuffer(lDMABufferLength,NULL); lDMABufferLength >>= 1; _DbgPrintF(DEBUGLVL_TERSE, ("lDMABufferLength = 0x%x", lDMABufferLength)); } while (!NT_SUCCESS(ntStatus) && (lDMABufferLength > (PAGE_SIZE / 2))); } if (NT_SUCCESS(ntStatus)) { ... AdapterCommon->WriteMCControlRegister((ULONG)PLAYBACK_DMA_CURRENT_BASE_ADDR, (ULONG)MyDmaChannel->PhysicalAddress().QuadPart); ... ------------------------------------------------------------ However no matter how we tried, we cannot get the audio sound out. We have seen in the debugger that all the register of our chip is now controllable and the address of the allocate addressed is sured can written to our audio chip. We have seen the sequence in the window such as: -------------------- [ValidateFormat] [SetNotificationFreq] [ServiceWaveISR] [SetState] -------------------- can be runned under the testing on debugger. I have seen from the MSDN help menu that for master channel, user need to use the API "copyto", "copyfrom" to copy data from and to the audio buffer. It seems that it is not necessary in the slave channel method. Is it really necessary in the master channel method? And how can I know the address of where the data come from when Window Media wave file? I have no method to fill in the parameter of the "copyto", "copyfrom" API to use them. Or anyone can post the reference code for masterchannel of Driver? Thans you very much Best Regards, Peter