DREQ not indicating for new data

Designing hardware that uses VLSI Solution's devices as slave codecs such as an external MP3 decoder chip for a host microcontroller.
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red_mamba
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DREQ not indicating for new data

Post by red_mamba » Mon 2011-04-11 8:25

The problem is that my DREQ line puts out a 50% duty with a frequency of around 12.5Mhz (or maybe its 12.288MHz as my xtal).

Which one of my setting are wrong? I want it to indicate when I can send more data to the decoder.
I'm using VS1053.

thank you!

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pasi
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Re: DREQ not indicating for new data

Post by pasi » Tue 2011-04-12 23:42

red_mamba wrote:DREQ line puts out a 50% duty with a frequency of around 12.5Mhz
Your xTEST pin is low or floating. Connect it to IOVDD.
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red_mamba
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Re: DREQ not indicating for new data

Post by red_mamba » Wed 2011-04-13 9:06

I have to check if it is a bad solder connection but my design has the xTEST pin connected to +3.3V

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Re: DREQ not indicating for new data

Post by red_mamba » Wed 2011-04-13 11:54

Found a hardware bug :D

The problem was that I used 2 PCB boards of an old projects and combined them.
I overlooked that DREQ line was connected to the output of the oscillator :mrgreen:

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pasi
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Re: DREQ not indicating for new data

Post by pasi » Wed 2011-04-20 20:30

red_mamba wrote:DREQ line was connected to the output of the oscillator
Sometimes you find the problems in unexpected places :-D
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Re: DREQ not indicating for new data

Post by red_mamba » Thu 2011-04-21 8:27

true true :mrgreen:

besides: experience is what you get when you don't get what you want :lol:

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Re: DREQ not indicating for new data

Post by red_mamba » Fri 2011-04-22 19:36

what would the reason be if the wav files are only noise and MP3 files aren't played at all no matter what bitrate. With MP3 DREQ line is allways +3.3V?

I have a 12.288MHz input frequency and the CLOCKF is set to 0x8430

p.s. The sine test is working, so the hardware and data, CS lines are working obviously.

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Re: DREQ not indicating for new data

Post by red_mamba » Sat 2011-05-07 18:17

still didn't solve this problem :cry:

checked all the signals and still can't figure out what the problem is.

can someone tell me what is the correct CLOCKF register data for 12.288MHz xtal?
I tried to change this a bit and can't make the chip to output any sound.
The only "sound" that is output is at playing WAV files. But the sound in unrecognisable. only chopping.

Need help :mrgreen:

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Re: DREQ not indicating for new data

Post by red_mamba » Mon 2011-05-09 7:46

Found the problem,

invalid MP3 data was stored in SPI FLASH memory when downloading it from PC :roll:

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