cyliax@ecn.purdue.edu (Ingo Cyliax) (03/24/91)
After pooring through all the literature on the sound and mic. ports and the DSP that I can find, I have come to the conclusion that there is no direct connection from the CODEC and the DAC to the DSP. I think it's all done with the DMA controller and the host port on the DSP. Is this correct ? Also, I haven't found anything on wether the serial ports from the DSP are used for anything internal on the NeXT. Is there a diagram or technical description of the hardware layout of the NeXT DSP, sound system and the DMA controller ? Has anyone thought of using the high speed serial ports from the DSP for anything besides hooking up CODECs, A/D or DACs ? One could design a serial port multiplexer or some high speed data channel to some other systems. ISDN anyone ? What's the max. DMA bandwidth between the DSP and host memory ? I would love to work on some projects involving the DSP on the NeXT. But right now I can't justify spending that much time on the NeXT, since I have other work to do that pays the rent.... Any comments ? -ingo /* Ingo Cyliax, Home: (317) 474-0031, E-Mail: pur-ee!flaubert!cyliax */
dank@nntp-server.caltech.edu (Daniel R. Kegel) (03/25/91)
I'm trying to find out how to write a program for the DSP that simply acts as a digital filter for audio. It would continuously read from the microphone, and write a processed version of the signal to the speaker. I do not want any part of the program to reside on the Unix side of the Next (except perhaps to load the DSP program). Can anybody tell me where to find example source code that accesses the sound ports from the DSP? I've looked through the examples that came with the Next, and found nice examples of how to write a DSP program that doesn't access sound, and nice examples of how to write a program that does sound but runs on the 680x0 rather than the DSP, but no examples of how to do sound with the DSP. Help! - Dan Kegel (dank@moc.jpl.nasa.gov)
kls30@duts.ccc.amdahl.com (Kent L Shephard) (03/25/91)
In article <1991Mar24.231144.19341@nntp-server.caltech.edu> dank@nntp-server.caltech.edu (Daniel R. Kegel) writes: >I'm trying to find out how to write a program for the DSP that simply >acts as a digital filter for audio. It would continuously read from the >microphone, and write a processed version of the signal to the speaker. >I do not want any part of the program to reside on the Unix side of the Next >(except perhaps to load the DSP program). > >Can anybody tell me where to find example source code that accesses the >sound ports from the DSP? I've looked through the examples that came with >the Next, and found nice examples of how to write a DSP program that >doesn't access sound, and nice examples of how to write a program that >does sound but runs on the 680x0 rather than the DSP, but no examples >of how to do sound with the DSP. I'm interested also. All I really need is the source code to the record or play object for the dsp. If anyone has this info please post. > >Help! >- Dan Kegel (dank@moc.jpl.nasa.gov) -- /* -The opinions expressed are my own, not my employers. */ /* For I can only express my own opinions. */ /* */ /* Kent L. Shephard : email - kls30@DUTS.ccc.amdahl.com */
jfreem@uncecs.edu (Joe Freeman) (03/26/91)
In article <1991Mar25.113606@ecn.purdue.edu> cyliax@ecn.purdue.edu (Ingo Cyliax) writes: >After pooring through all the literature on the sound and mic. ports >and the DSP that I can find, I have come to the conclusion that there >is no direct connection from the CODEC and the DAC to the DSP. I think >it's all done with the DMA controller and the host port on the DSP. Is >this correct ? > Yep. (I think you men pouring, unless you were commenting on the docs) The CODEC and the DACs are accesed via the DMA or host processor. You can request a stream from the CODEC or to the DACs and the driver will do all the buffer management. All data into and out of the DSP goes through the host port. >Also, I haven't found anything on wether the serial ports from the DSP >are used for anything internal on the NeXT. Is there a diagram or technical >description of the hardware layout of the NeXT DSP, sound system and the >DMA controller ? You don't really need to know the hardware layout but there should be a data diagram for it. Once again, the driver takes care of any communications. You have two choices. The host program can do practicly nothing and just set up the streams or it can manage each individ. buffer. > >Has anyone thought of using the high speed serial ports from the DSP for >anything besides hooking up CODECs, A/D or DACs ? One could design a serial >port multiplexer or some high speed data channel to some other systems. >ISDN anyone ? What's the max. DMA bandwidth between the DSP and host >memory ? I've done a 10 band graphic equalizer (moto app note port) and the PowerGlove driver. All via the external port. The DSP is the only way to guarentee real time performance. Because you own it. I've heard the max bandwidth is 2.5MB per sec but that doesn't leave any time for doing any filtering. The digital ears runs at 160K byte per sec. > -- Joe Freeman jfreem@uncecs.edu The opinions espressed here are my own and are not shared by my employer or anyone else I know of. Flames can be mailed to me or routed to /dev/null.
dejnsen@caen.engin.umich.edu (Nik Anthony Gervae) (03/27/91)
In article <1991Mar26.123538.29687@uncecs.edu> jfreem@uncecs.edu (Joe Freeman) writes: >In article <1991Mar25.113606@ecn.purdue.edu> cyliax@ecn.purdue.edu (Ingo Cyliax) writes: >>After pooring through all the literature on the sound and mic. ports >>and the DSP that I can find, I have come to the conclusion that there >>is no direct connection from the CODEC and the DAC to the DSP. I think >>it's all done with the DMA controller and the host port on the DSP. Is >>this correct ? >> >Yep. (I think you men pouring, unless you were commenting on the docs) Actually it's "poring", but who's keeping score. ;-) -- / Nik Gervae aka dejnsen@caen.engin.umich.edu | "It'll be finished next week, \ | CS/Linguistics stud. & NeRD at UM (go blow) | I promise!"--me | | | | | **When all else fails, bug someone who | "Just say an iguana chewed | \ knows (not me!). | up your textbook."--Jason Fox /
jfreem@uncecs.edu (Joe Freeman) (03/27/91)
PLEASE no more email about spelling or word choices. Yes I recognized an inappropriate word and then added one of my own. Someone said I should apologize. To whoever was offended, I will send a correctly worded response. via email. And don't tell me about poor (pour por) spelling in this one either. -- Joe Freeman jfreem@uncecs.edu The opinions espressed here are my own and are not shared by my employer or anyone else I know of. Flames can be mailed to me or routed to /dev/null.