Inside the iHP-120...
Feb 4, 2004 at 3:29 PM Post #31 of 40

Buckaroo Banzai

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Quote:

Originally posted by jpburton5150
...also are these the specs of a iHP-120 or iHP-100? because they have different amounts of buffer so probably have different hardware...


Hi,

you're right. in the ihp-100 is an smaller sdram chip installed.
harddisk too :wink:

the coldfire processor and all the other components are the same.

cheers
Juergen
 
Feb 11, 2004 at 12:13 PM Post #32 of 40

Buckaroo Banzai

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Quote:

Originally posted by Traveller
Last but not least, a look @ my a la cocktail-napkin, EE-Impared audio-trace. I'd like to think of it as an educated guess, but take it with a grain... no, make that a bag of salt. Family size.

Note: The UDA1380TT can transmit data from either the Decimator or Interpolator stages (hence the two paths to the I2S bus). Data is only received by the DSP group.




It's been real & it's been fun, but...
cool.gif



Hi Traveller,

I've read some datasheets and manuals of the UDA1380.
The 1380 is responsible for the handling of the digital out and in
connectors. The digital out can be either slave and master. I think
iriver didn't implement these master/slave feature.

Quote from the 1380 datasheet (page 20):

8.13.1 DIGITAL AUDIO INPUT INTERFACE
The digital audio input interface is slave only, meaning the
system must provide the WSI and BCKI signals (next to
the DATAI signal).
Either the WSPLL locks onto the WSI signal and provides
the internal clocks for the interpolator and the FSDAC, or
a system clock must be applied which must be in
frequency lock to the digital data input interface signals.

8.13.2 DIGITAL AUDIO OUTPUT INTERFACE
The digital audio output interface can be either master or
slave. The data source for the data output can be selected
from either the decimator (ADC front-end) or the digital
mixer output.

Your D-I and D-O on your cocktail-napkin must be placed on
the UDA1380. The communication between 1380 and MCF5249
runs over the I²C Bus.

Some more infos will follow in a couple of days.

Cheers
Juergen
_______________________________________________
iHP@Lounge
www.ihplounge.com
 
Feb 11, 2004 at 5:35 PM Post #33 of 40
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...so does the s/pdif in/out connect to the DSP section of UDA1380? I assume the I2S signal has to have something done to it before it 'becomes' S/PDIF...right?

/andrew - got his iHP140 monday, but is not about to look at its guts...
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Feb 12, 2004 at 12:30 PM Post #34 of 40

Traveller

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Quote:

Originally posted by Buckaroo Banzai
Hi Traveller,

I've read some datasheets and manuals of the UDA1380.
The 1380 is responsible for the handling of the digital out and in
connectors. ... The communication between 1380 and MCF5249
runs over the I²C Bus.


Juergen, you couldn't have based all of your conclusions on the two paragraphs from the documentation alone. So what else did you read that clearly rules out I2S comm. between UDA1380 & ColdFire? You are also implying that the S/PDIF components of the Coldfire are not used, correct?

This finally suggests that the digital Receiver-Transmitter circuits take S/PDIF & convert it to I2S for the UDA1380. Yet, I didn't see you post any on the list of chips found on the iHP-120....

Last but not least, I was fairly certain that I2C was purely a control path & not for digital audio signals...?!? That the UDA1380 handles digital I/O is clear but digital I/O to what - that's the part that's not all that clear (to me, anyways
tongue.gif
)

Yes, looking forward to more info, lots more
wink.gif
 
Feb 13, 2004 at 7:58 AM Post #35 of 40

Buckaroo Banzai

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Hi Traveler,


You're right. The I²C-bus is for LCD/LED-, keypads-, converter-
and EEPROM-controls and A-to-D-, D-to-A converters.

My "bus" fault. :wink:


The MCV5249 got analog/digital audio-I/Os channels and the
UDA1380 too. I've checked the MCF5249 evaluation board circuit
block-diagram and there's no direct use of the MCF5249 IEC958
I/O channels on it. So which layout uses iriver?


1) Serial audio interfaces (IIS/EIAJ)

or

2) Digital audio interfaces (IEC958)


I think iriver uses the serial audio interfaces (I²S bus) only (1.5.9).
On the circuit layout, the UDA1380 is placed near the digital and
analog connectors.


An short cut out of the Product Brief, MCF5249PB/D, Rev. 0, 3/2002

1.5.9 Serial Audio Interfaces
The MCF5249 digital audio interface provides four serial Philips IIS/Sony EIAJ interfaces. One interface
is a 4-pin (1 bit clock, 1 word clock, 1 data in, 1 data out), the other three interfaces are 3-pin (1 bit clock,
1 word clock, 1 data in or out). The serial interfaces have no limit on minimum sampling frequency.
Maximum sampling frequency is determined by maximum frequency on bit clock input. This is 1/3 the
frequency of the internal system clock.

1.5.10 IEC958 Digital Audio Interfaces
The MCF5249 has two digital audio input interfaces, and one digital audio output interface. There are four
digital audio input pins, two digital audio output pins. An internal multiplexer selects one of the four inputs
to the digital audio input interface.
There is one digital audio output interface but it has two IEC958 outputs. One output carries the professional
“c” channel (Channel Status), and the other carries the consumer “c” channel. All other bits (audio data, user
channel bits, validity flag, etc) are identical.
The IEC958 output can take the output from the internal IEC958 generator, or multiplex out one of the four
IEC958 inputs.

1.5.11 Audio Bus
The audio interfaces connect to an internal bus that carries all audio data. Each receiver places its received
data on the audio bus and each transmitter takes data from the audio bus for transmission. Each transmitter
has a source select register.
In addition to the audio interfaces, there are six CPU accessible registers connected to the audio bus. Three
of these registers allow data reads from the audio bus and allow selection of the audio source. The other three
registers provide a write path to the audio bus and can be selected by transmitters as the audio source.
Through these registers, the CPU has access to the audio samples for processing.
Audio can be routed from a receiver to a transmitter without the data being processed by the core so the
audio bus can be used as a digital audio data switch. The audio bus can also be used for audio format
conversion.

END CUT ----------------

I've read some sections of the MCF5249 user manual. So mobil audio designer can program (activate)
the IEC985 or the I²S (or use both?)

With the I²S bus they are a more compatible to other I/O techniques ... I guess. :wink:


cheers Juergen

iHP@lounge
www.ihplounge.com
 
Feb 25, 2004 at 6:21 PM Post #36 of 40

Traveller

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Quote:

Originally posted by Buckaroo Banzai
... Some more infos will follow in a couple of days.


Hey, nothing new to report? Sniff...
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Feb 26, 2004 at 5:39 PM Post #37 of 40
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while the subject is on S/PDIF:

i'm eventually going to want to build my own DAC...any recommendations for this? it doesn't have to be 'portable' per se, but i'd like to be able to put it on my desk at work, and pack it away in a file drawer at night.

is the portable DAC project on headwize a worthwhile endeavor?

/andrew
 
Jan 17, 2005 at 2:57 PM Post #39 of 40

lukelukeluke

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Did some testing over the weekend with an idea in mind. It turns out that the 3V out pin on the remote looks to be directly connected to the internal buck boost converter. So, you've got a pretty hefty 3.3V source for any peripherals you may want to hack on there.

Be careful hacking the remote, though. The (probably) flyback converter for the EL backlight was putting out 70VAC on my player.
 

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