memory

Hi dazheng,

forget the EEPROM.ive got something better

i have already implemented ADPCM successfully,the
problem i am having with MMC card interfacing is that
when i try to record compressed voice data on MMC
card,the voice upon retrieval from the card at PC end
gives a jerk after 2-3 seconds of voice play back
may be this jerk is due to sector change ,every sector comprises 510 bytes

What i am trying to design is, the 83TF892 takes
analog input data ,performs A/D conversion ,which
generates 11-bit data samples at rate of 7.2KHz ,these data samples are then subjected to ADPCM speech compression which (?) generates 4 bit compressed data
sample from 16-bit data sample ,then it takes other uncompressed data sample and compresses it to 4-bit ADPCM compressed data sample
These two data samples are then packed in a single byte,this byte containing two ADPCM data sample is then written to MMC card.This is recording process
once we are done with recording ,we need to retrieve the data , For retrieval the Micrcontroller reads compressed voice data from MMC sector by sector and transmits it to PC through serial port
which is recorded on pc in binary file
this binary file is decompressed using JavaC and then decompressed and converted to wave file through more JavaC code

can you help with any of it?

Thanks

zuisti

Hi dazheng,

forget the EEPROM.ive got something better

i have already implemented ADPCM successfully,the
problem i am having with MMC card interfacing is that
when i try to record compressed voice data on MMC
card,the voice upon retrieval from the card at PC end
gives a jerk after 2-3 seconds of voice play back
may be this jerk is due to sector change ,every sector comprises 510 bytes

What i am trying to design is, the 83TF892 takes
analog input data ,performs A/D conversion ,which
generates 11-bit data samples at rate of 7.2KHz ,these data samples are then subjected to ADPCM speech compression which (?) generates 4 bit compressed data
sample from 16-bit data sample ,then it takes other uncompressed data sample and compresses it to 4-bit ADPCM compressed data sample
These two data samples are then packed in a single byte,this byte containing two ADPCM data sample is then written to MMC card.This is recording process
once we are done with recording ,we need to retrieve the data , For retrieval the Micrcontroller reads compressed voice data from MMC sector by sector and transmits it to PC through serial port
which is recorded on pc in binary file
this binary file is decompressed using JavaC and then decompressed and converted to wave file through more JavaC code

can you help with any of it?

Thanks

zuisti

If you generate audio data at 7.2kHz - what do you think will happen if your PC can't play at that odd speed, and instead consume them at 8kHz speed?

zuisti,

ignoer the info from the trollops!

i thin kthe problem is you have a sector of 510 bytes.but mostly it is 512.

ya, im a wheel coder man. hahahaha

But ive got a problem with this now(?) so maybe you help me ;)

I make a simple ISOS DRSN file to toggle LED on PortD.4. I just connect 2 button on PortB. One button PortB.4 as reset button. PortB.7 as toggle swicth. I also put a delayMS = 500 as protection from button bounceying.

My question,

1. How to make LED toggle on rising edge instead of MCU have to scan the state condition of the button and respond according if.. then statement. That mean (for edge rising signal ... 0 to 5V) MCU been triggered by rising edge of signal from low to high or hight to low or high to high.

2. I'm using Xtal = 31Mhz ... and I dont connect any crytal (actually I want to use internal oscilator with PLL ) .... how to write the code for that ? any example ?

Thanks for any helps.

"i thin kthe problem is you have a sector of 510 bytes.but mostly it is 512."

Mostly 512? Check the spec again. What about the 518-byte sectors?
And what about the 502-byte, 554-byte, and the jumbo 1024-byte sectors?
We've got to handle those too. It's all there in section 3.1.4.1.59.

"1. How to make LED toggle on rising edge instead of MCU have to scan the state condition
of the button and respond according
if.. then statement. That mean (for edge rising signal ... 0 to 5V) MCU been triggered by
rising edge of signal from low to high or hight to low or high to high."

Qualify the if/then with an X/OR of the LED input and TMR0's MSB.
Trigger is best by rising edge of signal low to low.

"2. I'm using Xtal = 31Mhz ... and I dont connect any crytal (actually I want to use internal oscilator with PLL ) .... how to write the code for that ? any example ?"

You're in luck. I've already done the code for that. I made a development branch
off of mainline and checked osc_cfg.c into Perforce.

dazheng,

your a great programmer man.sector size woz wrong!

Rego has been working now on a conversion to Proton Basic (I don't have skills about MCU basics yet, as I wrote).
I somebody want to do this, my C source is simple and easy to understand I think...

i like your project much,and it is a good effort from
u (converting it to JavaC project) but how about writing a (v.b interface to it) it will
be very cool....

also did u test the real hardware (ig is there any problem in led power or anything like this)

this project can be upgraded with many opinons..

But ... my dear friend, please post your minds, repairs and opinions here!

"your a great programmer man."

Not true!

I am a great programmer.

"... my C source is simple and easy to understand I think."

Yeah, "you think", but you're wrong.

I've shown code from both of you around the shop here. They just laugh.
It's really pretty sucky code. No wonder the prototype is so unstable.

dazheng,

now i got a hard question for yew hardware guru......

I need to choose a capacitor. Does you know how to choose right capacitor for example if we want to use 100 uF caps but with what suitable voltage because when we want to buy caps, the supplier asks "what voltage?"

i asked Rego and he says:

you need to know the maximum voltage across the capacitor in your application . for example if you put the capacitor in parallel with the voltage source, you choose the voltage capacitor higher than the voltage source. Vsource=12V -> Vcap=16V tipical values of voltage are 6.3V, 16V, 50V this are normalized And you need to know the maximum current in your application. For example if your power supply is for 1A current it might be nessesery to take 100uF capacitor for higher voltage because they are more powerfull and you will can get hier curr ent from them and can blow youre socks off!

is he right?

Note
This message was edited to reduce width.

you
need
to
know
the
maximum
voltage
across
the
capacitor
in
your
application
.
for
example
if
you
put
the
capacitor
in
parallel
with
the
voltage
source,
you
choose
the
voltage
capacitor
higher
than
the
voltage
source.
Vsource=12V
->
Vcap=16V
tipical
values
of
voltage
are
6.3V,
16V,
50V
this
are
normalized

And
you
need
to
know
the
maximum
current
in
your
application.
For
example
if
your
power
supply
is
for
1A
current
it
might
be
nessesery
to
take
100uF
capacitor
for
higher
voltage
because
they
are
more
powerfull
and
you
will
can
get
hier
curr
ent
from
them
and
can
blow
youre
socks
off!

Of course he is right.

Too low voltage on your cap and you will loudly hear it protest!

Too high ripple current on your cap and it will get too hot.

It's only in school books you may talk about ideal components. In real life, there are always more than one parameter to specify when selecting components.

Some i, eh poster posted using pre !pre or some other 'technique' making it a pain in the gluteus maximus to read all entries.

Anyhow the post has wandered off, I do not see what camacitor voltage has to do with the original subject.

Erik

The original subject?

Oh, you mean the use of this forum as a private message board?

If the Keil staff just press delete on this kind of threads, people will learn - or at least select other sites.

I sure hope the thread DOESN'T end. How often is it that the rest of us can get an "inside" look at the caliber of programming used by such industry giants as Mattel?

These guys are geniuses! I just hope that they collaborate on a book!

You know...if you take the brain power of these two guys and just figure out a way to harness it...you might be able to toast bread! Lightly.

There are more than one way to toast bread. The only common part is the required heat and the burning smell :)

Hi dazheng,

hope you had a good weekend.I saw you're sister over at the mall on saterday.i was waring a teeshirt ;-)

The latest work is a verrrry Interesting Project... and I really like it very much...... I know saying thank you is not enough for your hardwork and cleverness at doing this project..... but thats all i can do for the now.

I have build an app to work with the lovely app from jenjen.

Can you test it because i have very limit time now and tell me if working ?

Also if you want anything to add.

file is at the usual place.

The upload has problem or it limitation ?

yes i think the system could crash, but in my project i only use the lpt & the screen. if you think that the system would be stable. But my questions is what happens with MCU, maybe MCU dont like working without interruptions.i don't need to get back to MCU once my programm has finished.

this is like an embedded project the pc only has to show the signal from the picture in the screen.

Thanks

zuisti

Hi "zuisti",

ya, i know you saw her.our mum wasnot happy :O

Thanks for the compliments. but remember that the project wouldnt be so good if you werenot there to give me good profesional help and advise. i trust Your wisdnom and experience .

Rego was near right with capacitor. but he is not so profesional and right always ;)

best advise is have a capacitor that is biger for what you need. so if you need 50poofs you can use 100poofs (or more) and it will be ok. you MUST connect the right way or they pop!

your friend,

dazheng

No, poof capacitors (pF) are not polarized.
Poff capacitors (electrolytes and tantals) are polarized.

The question here isn't if the capacitance should be doubled, but what voltage it should be, and if the ripple current is high enough that the ESR must be considered.