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Problem with mp3 decoding and lack of cpu power solved

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  • berin1279
    Ok, here is the problem, an ARM processor running at 90mhz runs at like 98% usage to decode a 128bit mp3. OK well that really kind of sucks if you need or wnat
    Message 1 of 6 , Mar 1 1:02 AM
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      Ok, here is the problem, an ARM processor running at 90mhz runs at
      like 98% usage to decode a 128bit mp3. OK well that really kind of
      sucks if you need or wnat to do any thing else. Ok well probelm
      solved, as far as I can tell. Every one seems to have the same basic
      idea's of what they would like the zipits to do. and this is in
      order of the MOST wanted needed.

      1: IRC
      2: YAHOO,MSN,AOL IM, WHAT EVER OTHER NAME CHAT SYSTEM.
      3: SSH CLIENT/server
      4: MP3'S here is what my idea comes in
      5: wifi hotspot locater
      6: very light internet web browsing
      7: what ever else... fill in the blank 8,9,10.....
      tipical linux box applications

      Ok the problem is that it has a rather very weak processor for
      playing music, but we have an easy method for adding GIGS of storage
      to the system already. PROBLEM sovled. there is an onboard audio
      chip which takes digital audio in. Ok so where already all in the
      works to design an add on board with extra things like serial
      backlighting ETC.... flash drives all in one. lets add one more
      thing to keep this system running top knotch. oh and this may break
      the bank at $17. :) the zipit has I2C already so i2c plus a data
      line and a few components and you have your mp3 decoder.

      http://www.pjrc.com/mp3/sta013.html not the best choice maybe but
      it is 3v operation.
      http://www.micronas.com/products/by_function/mas_3587f/product_inform
      ation/index.html This one has encoding/decoding ablity which would
      make it possable to do VOIP the easy way.

      ok so lets take the processing load off of the cpu and put it on
      dedicated hardware. Then mp3ing from ether local source, or
      streaming audio media it would keep the zipit TRUCKING strong with
      out bogging to death.

      So in conclusion, on some other post I mentioned that we should use
      a PIC chip for a multi use system. one pic chip could use 2 IO lines
      from the zipit. one for RX and for TX, ok so we now have 2 high
      speed input outputs. Where looking to add a back light but we also
      have a bunch of options that may be an option to add like conroling
      the backlight brightness and maybe color. OK so use the pic to
      control some logic that deals with the inverter functions. Ok so
      still use that same pic chip with a NiCad Battery pack that can not
      pump power back into the zipit. Well if the pic chip is running
      functions to control stuff but its battery backed up with a seperate
      battery other then the main battery we may as well add the CODE for
      a real time clock. Now also the idea of adding an MP3
      decoder/encoder chip. small simple inputs/outputs digital signal. ok
      so pump the data stream threw the pic chip to from, and the audio is
      then sent out the zipits onboard audio amp system. That gives us
      control over the volume as well. The last things to add is the flash
      disk socket, and the EL backlight driver which will give a grand
      total of 4 mod's added to the system. I my self am not planning to
      add a serial chip to the system but a cut out in the wall of the
      battery compartment with a 6pin header and one pin missing for a
      KEY. it wont block the option for a larger battery in any way but
      still give me a serial port to an external serial max233 adapter if
      i need one. Basicly meaning if I want to plug into the onboard
      serial I'll have to remove the battery. I have faith that the 2 back
      ports are some kind of TTL serial in the first place so I'm not
      going to spend my time dicking around with trying to add USB or
      onboard serial to the system because I can not find any useful
      function for even adding it to such a small device. and those 2
      ports may already be just want were looking for or even better what
      where looking for but running at a higher speed then serial in the
      first place.

      If I have to make a gues I'm going to claim one of the ports would
      be dedicated to an external network adapter for wired network. the
      other would be used for some kind of external device mouse, hardware
      mp3 decoder, file transfer to pc? serial usb what ever??? hell maybe
      even a bluetooth adapter. I'm thinkign along the lines of plugging
      into an ADAPTER. The one thing I think would be a nice touch though
      would be an adapter which plugs into the PC'S usb port and threw
      what ever means plugs into one of the ports on the back of the
      zipit. AND if the pinouts work right use the 5v from the PC to
      charge/power the zipit so as to save from carrying the wall wart
      around.
    • Lumkichi
      Sorry for the post -- I m a long time lurker... Your ARM processor probably has enough room to comfortably decode 128kbps MP3 s. Our DMP1 car mp3 player has
      Message 2 of 6 , Mar 1 4:46 AM
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        Sorry for the post -- I'm a long time lurker...

        Your ARM processor probably has enough room to comfortably decode 128kbps MP3's.  Our DMP1 car mp3 player has the 90 Mhz EP7312 CPU and it decodes 320kbps MP3's just fine while maintaining a rlogin session or a dropbear connection.  The stock firmware can also decode DRM-protected WMA's and play up to 320kbps as well.  At those rates, it's pretty busy but it's mostly disk access (we have 20 GB on which to HDD's to store music)

        So..., give it a shot.  You might be surprised what your Zipit can do.

        ~lum

        On 3/1/06, berin1279 < berin1279@...> wrote:
        Ok, here is the problem, an ARM processor running at 90mhz runs at
        like 98% usage to decode a 128bit mp3. OK well that really kind of
        sucks if you need or wnat to do any thing else. Ok well probelm
        solved, as far as I can tell. Every one seems to have the same basic
        idea's of what they would like the zipits to do. and this is in
        order of the MOST wanted needed.

      • berin1279
        Look up the spects on the EP7312, as aposed to the ARM720T which is in the zipit. your processor is a more capable processor aimed at compressed audio, though
        Message 3 of 6 , Mar 1 8:44 AM
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          Look up the spects on the EP7312, as aposed to the ARM720T which is in
          the zipit. your processor is a more capable processor aimed at
          compressed audio, though having nearly identical spects. the EP7312
          has more hardware processing ablity onboard like realtime clock
          hardware wma pre decoding etc......... its also a much newer processor
          and larger processor.
          The ARM720T was orignaly designed for medical use apps. needing to
          have the ablity to monitor and display results in portable devices.
          like EKG'S for example.
          I'd be intrested to see the results from any one here that has the mp3
          decoders compiled already play a 320kbit mp3 on there zipit.
          considering a pentium 90 that I had as a linux mp3 player had problems
          with that bit rate. later moved to a 166mmx and all was good. The
          problem wht the 90mhz pentium and that extream bit rate was with the
          multi tasking. it would play fine till you tryed to access the file
          server which the system was as well. but it was also a soft router, on
          DIAL up so the problem was with the speed of the processor.
        • Lumkichi
          I C. I do have an email from ZipItPet dated 4/24/2005 that your Zipit uses a EP7312-CR-90 processor. Could I be mistaken on this? I don t know how it
          Message 4 of 6 , Mar 1 9:01 AM
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            I C.

            I do have an email from ZipItPet dated 4/24/2005 that your Zipit uses a EP7312-CR-90 processor.  Could I be mistaken on this?  I don't know how it compares with our little processor, but they do sound like the same.  And as far as I understand, I think the EP7312 processor mimics the ARM 720T because for the longest time, I thought that's what we had as well until we opened the unit up.  The diagnostics identifies itself as ARM 720T, not as EP7312 which is what it really is.

            We do have an on-board RTC, but we do not use it at all.  It draws too much power for a car battery, so we rely on a low-power PIC to provide the same functionality--it is used to power on the system in the middle of the night for a nightly wireless sync of new music and podcasts.

            ~Lum

            On 3/1/06, berin1279 <berin1279@...> wrote:
            Look up the spects on the EP7312, as aposed to the ARM720T which is in
            the zipit. your processor is a more capable processor aimed at
            compressed audio, though having nearly identical spects. the EP7312
            has more hardware processing ablity onboard like realtime clock
            hardware wma pre decoding etc......... its also a much newer processor
            and larger processor.

          • berin1279
            good catch I feel dumb :), lot on my mind. ... uses a ... know how it ... same. And as ... 720T ... until we ... 720T, not as ... too much ... the same ...
            Message 5 of 6 , Mar 1 12:51 PM
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              good catch I feel dumb :), lot on my mind.

              --- In zipitwireless@yahoogroups.com, Lumkichi <lumkichi@...> wrote:
              >
              > I C.
              >
              > I do have an email from ZipItPet dated 4/24/2005 that your Zipit
              uses a
              > EP7312-CR-90 processor. Could I be mistaken on this? I don't
              know how it
              > compares with our little processor, but they do sound like the
              same. And as
              > far as I understand, I think the EP7312 processor mimics the ARM
              720T
              > because for the longest time, I thought that's what we had as well
              until we
              > opened the unit up. The diagnostics identifies itself as ARM
              720T, not as
              > EP7312 which is what it really is.
              >
              > We do have an on-board RTC, but we do not use it at all. It draws
              too much
              > power for a car battery, so we rely on a low-power PIC to provide
              the same
              > functionality--it is used to power on the system in the middle of
              the night
              > for a nightly wireless sync of new music and podcasts.
              >
              > ~Lum
              >
              > On 3/1/06, berin1279 <berin1279@...> wrote:
              > >
              > > Look up the spects on the EP7312, as aposed to the ARM720T which
              is in
              > > the zipit. your processor is a more capable processor aimed at
              > > compressed audio, though having nearly identical spects. the
              EP7312
              > > has more hardware processing ablity onboard like realtime clock
              > > hardware wma pre decoding etc......... its also a much newer
              processor
              > > and larger processor.
              >
            • M. Warner Losh
              Re the EP7312: http://www.cirrus.com/en/products/pro/detail/P139.html This is a ARM720T chip with DAI (Digitial Audio Interface) and LCD controller. Warner
              Message 6 of 6 , Mar 1 12:56 PM
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                Re the EP7312:

                http://www.cirrus.com/en/products/pro/detail/P139.html

                This is a ARM720T chip with DAI (Digitial Audio Interface) and LCD
                controller.

                Warner
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