Devendra, thanks very much for your insight. Since I used a different source base than the DDK sample, I'll check it out to see how it would map to my case. Again, thanks very much for your reply. I'll post the results here. I had actually started porting over to IMiniportMidi, but now I'll try this out first. Philip Lukidis ----- Original Message ----- From: BlazeAudio Developer To: wdmaudiodev@xxxxxxxxxxxxx Sent: Thursday, November 27, 2003 11:30 PM Subject: [wdmaudiodev] Re: question on DMUS UART Philip, I ran into a very similar problem (it also happens to be a 1394 device!!). The way we worked around it was not to call GetMessage/PutMessage directly from our DPC, but to actually call the DMUS Port's Notify routine. Which in turn invokes the stream's SourceEvtsToPort method which does the real work. You might still want to get the time-stamp from your DPC. Hope this helps. Thanks. Devendra. At 03:10 AM 11/27/2003, Philip Lukidis wrote: Hi. I have a DMUS UART capture miniport (over 1394), and it works great with 1 CPU (on Win2k SP4 and WinXP SP1). The moment I switch to dual CPUs on either OS I the same problem. The design is very simple. I send only uncooked MIDI bytes up to the sink as they become available, one at a time (when I buffer and send cooked data I have the same issue, as described below). Each time I call PutMessage on the sink, I fill up the DMUS event as follows (error checking removed): (called from a DPC, and after having acquired a spinlock): status=pThis->m_AllocatorMXF->GetMessage(&pEvent); memcpy(pEvent->uData.abData,pMessage,usLength); pEvent->cbEvent=usLength; pEvent->pNextEvt = NULL; pEvent->usChannelGroup = 0; pEvent->usFlags = DMUS_KEF_EVENT_INCOMPLETE; // uncooked status=pThis->m_pMiniport->m_MasterClock->GetTime(&pEvent->ullPresTime100ns) ; status=pThis->m_sinkMXF->PutMessage(pEvent); Simple enough. I always get the following bugcheck (see below for a trace as well as the bugcheck). Is there a known issue here with DMUS ports/portcls, or, if not, can anyone suggest anything? Can I call the allocator at DISPATCH? Can I call PutMessage on the sink at DISPATCH? I tried doing this in a worker thread, but got the same results. If anyone has any ideas, please share. Thanks. Philip Lukidis PS: I had Driver Verifier on, with all options except low resource simulation, and verified portcls and my own drivers. With or without DV I had the same problem. 1: kd> !analyze -v **************************************************************************** *** * * * Bugcheck Analysis * * * **************************************************************************** *** DRIVER_IRQL_NOT_LESS_OR_EQUAL (d1) An attempt was made to access a pageable (or completely invalid) address at an interrupt request level (IRQL) that is too high. This is usually caused by drivers using improper addresses. If kernel debugger is available get stack backtrace. Arguments: Arg1: 00000002, memory referenced Arg2: 00000002, IRQL Arg3: 00000000, value 0 = read operation, 1 = write operation Arg4: f7648de7, address which referenced memory Debugging Details: ------------------ READ_ADDRESS: 00000002 CURRENT_IRQL: 2 FAULTING_IP: portcls!CPackerMXF::ProcessQueues+64 f7648de7 0fb74a02 movzx ecx,word ptr [edx+0x2] DEFAULT_BUCKET_ID: DRIVER_FAULT BUGCHECK_STR: 0xD1 LAST_CONTROL_TRANSFER: from 8042aa0f to 804564d0 STACK_TEXT: eb427b58 8042aa0f 00000003 eb427ba0 00000002 nt!RtlpBreakWithStatusInstruction eb427b88 8042b002 00000003 00000002 f7648de7 nt!KiBugCheckDebugBreak+0x31 eb427f14 8046987c 00000000 00000002 00000002 nt!KeBugCheckEx+0x390 eb427f14 f7648de7 00000000 00000002 00000002 nt!KiTrap0E+0x284 eb427fb8 f7648853 a6203fc4 a699fff0 f76487f4 portcls!CPackerMXF::ProcessQueues+0x64 eb427fc4 f76487f4 f764330e a698be90 820a8000 portcls!CPortPinDMus::ServeCapture+0x33 eb427fc8 f764330e a698be90 820a8000 aeda5f48 portcls!CPortPinDMus::RequestService+0x22 eb427fdc 80465728 a6203fa0 a6203f90 00000000 portcls!CServiceGroup::ServiceDpc+0x29 eb427ff4 8046ab4b eb447b18 00000000 00000000 nt!KiRetireDpcList+0x47 FOLLOWUP_IP: portcls!CPackerMXF::ProcessQueues+64 f7648de7 0fb74a02 movzx ecx,word ptr [edx+0x2] FOLLOWUP_NAME: MachineOwner SYMBOL_NAME: portcls!CPackerMXF::ProcessQueues+64 MODULE_NAME: portcls IMAGE_NAME: portcls.sys DEBUG_FLR_IMAGE_TIMESTAMP: 3e9cd7ea STACK_COMMAND: kb BUCKET_ID: 0xD1_portcls!CPackerMXF::ProcessQueues+64 Followup: MachineOwner --------- ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/ ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.de/