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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: Astral on September 08, 2013, 05:45:42 AM
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I've got myself a MASPlayer here connected to the stock parallel port on my A1200. It's limitations are pretty well known with high rate MP3's. So...I thought I'd buy an IOBlix 1200P to see if higher rate MP3's could work through this.
No luck in setting it up.
Obviously the main thing is letting MASPlayer know I would like to use the IOBlix device driver. But so far no luck. I am not even sure if it is configurable to use this device.
Has anyone been successful in this? Or even some other similar setup in the MASPlayer is working through another device other than the stock parallel port?
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The MAS Player can only used on an orginal parrallel ports.
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Mmmmmmm...interesting. The MASPlayer driver disk contains the sourcecode. Not sure what language it is in - I can check. I am not much of a coder, but would it be possible to reprogram it to work/access a different .device?
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Mmmmmmm...interesting. The MASPlayer driver disk contains the sourcecode. Not sure what language it is in - I can check. I am not much of a coder, but would it be possible to reprogram it to work/access a different .device?
It depends on how the hardware was designed and what the other parallel port is capable of. It might require directly accessing the other hardware as the device may not offer enough functionality.
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Newer MAS chips also support AAC/MP4 Audio, but that is suitable for connection to slot CPU.
http://www.alldatasheet.com/view.jsp?Searchword=MAS35
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Are you saying that the rate limiting factor is not the decoding done on-chip in the MAS device, but the speed at which the data is fed to it?
As best as I recall, when done by the 680X0 CPU the decoding was the rate limiting factor using up to 50+% of even an 060. But I'm no expert in this area.
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Are you saying that the rate limiting factor is not the decoding done on-chip in the MAS device, but the speed at which the data is fed to it?
As best as I recall, when done by the 680X0 CPU the decoding was the rate limiting factor using up to 50+% of even an 060. But I'm no expert in this area.
The opinion I've gathered in recent times says that yes, in more peoples opinions than not, it's the parallel port speed that is the limiting factor. Mind you...I haven't done tests to confirm this.
That's why I'm thinking the IOBlix1200P (or for other miggies a similar device) would help.
I'm also beginning to think that maybe an MP3@64 would've been a better choice for me???
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The opinion I've gathered in recent times says that yes, in more peoples opinions than not, it's the parallel port speed that is the limiting factor. Mind you...I haven't done tests to confirm this.
You probably should confirm it, if there is a problem with speed it's more likely going to be because the CPU can't guarantee that data will keep flowing to the chip all the time.
But it might depend on what the protocol is doing, if it's having to reverse direction on some pins constantly then the built in parallel port might not be able to keep up. But your add on parallel port might not be any better.
Ideally you want a parallel port that can constantly DMA to the MASPlayer without any interaction from the CPU. I don't know of any DMA parallel ports though.
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I believe that the parallel port was not intended to do much more than transfer 8-bits to a printer; while it has been used for Zip drives, AV A-to-D digitizers and the MAS device, that was not its designed purpose. DMA to a high speed parallel "pipe" occurs for SCSI, but PIO is used on IDE. The other DMA devices are serial in nature. In any event, you are using the Amiga as a storage device to feed data to an MP3 chip and there are choices made based on cost and simplicity. PIO is also used in place of DMA for serial USB and Ethernet devices (see Jens' articulation on EAB).
The function you desire would be best handled with a sound card with the desired decoding chips in situ.