DMA 8237

[mitulatbati]

Hi

Have you ever programmed the 8237 DMA controller? I have a dll, which assures direct access to all the registers. I programmed everything as it is described in:

http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/dma.html and

http://inversereality.org/tutorials/sound%20programming/dmaprogramming.html

Of course I have done it in LabView. And just doesn´t want to work.

Ideas?

Thanks

Mitulatbati

[RamonaL]

Hi!

You give not a lot of information. What exactly is not working? Do you get an error message? Do you have a example code? Which dll are you using? Are you sure, the dll is working fine?
Without more information it is quite hard to help you!

Thanks, RMathews

[mitulatbati]

Hi,

Ok, let me clear the things. I have a dll, which enables direct access to all the registers. This dll I have downloaded from

http://www.entechtaiwan.com/dev/hw32/index.shtm

The TVicHW32.dll is used, more exact, the SetPortByte() and the GetSysDmaBuffer() functions. GetSysDmaBuffer() allocates a space in the memory for the DMA transfer.

I allocate the memory, then set the DMA registers according to the above mentioned documentaton, then enable the DMA channel (channel 5, 16 bit transfer). My external device wants already to transfer its data to the PC via DMA, but nothing happens.

I expect, that the register addresses are correct. As I read, these addresses are standard since middle of the 80´s.

LV 7.0.

regards

MB

[RamonaL]

Hi Mitulatbati!

Unfortunaltly I cant run your VI. Can you please attach the TV_SetPortByte.vi as well?

Thank you!
RMathews

[mitulatbati]

Hi Rmathews,

I just put the CIF´s into the vi, now it is readable without TV_SetPortByte.vi

Thanks for the effort, I hope you find out somoething.

MB