Microphone to PIC

[mister_e]

There's still the option to use a PIC with 2 comparator and set their reference with resistors , trim pot OR HPWM. I like the HPWM stuff... full control of the beast... and when you want

Now you just need an amplifier/Microphone and poll the comparator output to know what's happen.

[scaenix]

There's still the option to use a PIC with 2 comparator and set their reference with resistors , trim pot OR HPWM. I like the HPWM stuff... full control of the beast... and when you want

Now you just need an amplifier/Microphone and poll the comparator output to know what's happen.

I don't quite get what polling the comparator means!

[mister_e]

to do simple... read the comparator output.

If Comparator1=1 then Goto GotSoundFromLeftEar
If Comparator2=1 then Goto GotSoundFromRightEar

where Comparator1 and Comparator2 represent dedicated I/Os OR internal register (like CMCON for a PIC16F628A and/or PIC16F88)

[scaenix]

ok got that! thanks very much!

[scaenix]

There's still the option to use a PIC with 2 comparator and set their reference with resistors , trim pot OR HPWM. I like the HPWM stuff... full control of the beast... and when you want

Now you just need an amplifier/Microphone and poll the comparator output to know what's happen.

Sir, if this method is to be done, how should I place the microphone? front or facing left and right as said in the previous post?

[mister_e]

it will depend of what type of mic you are using. A good unidirectional is suggested but you can use an omnidirectional and hack it's pattern.

with both, you need to place them in such way they will detect ONLY what you want to. Hence, face left, and face right.

Maybe you could try midpoint between right and middle, midpoint between left and middle.

With some experiment you should find the best match.

[scaenix]

How about this link sir?

http://www.extremenxt.com/sound.htm

the creator of the project said that the circuit is a simple sound sensor but I can't quite figure out the purpose of the diode array with the label RCX. I tried to look for a way to contact the creator of the project but I didn't find any. I know that the circuit is made for RCX from Lego Mindstorms, but I just want to know how to use this sensor for a PIC, specifically 16F84A, so that I could make a PBP program for my project. Any help would be gladly appreciated. Thanks in advance.

[mister_e]

the diode thingy is use to supply the OP-AMP AND also use to modulate the OP-AMP signal to the supply line. I don't know how the RCX handle it but to me , for your application it's way too complicated.


Now if you want to use this grand'pa 16F84, you will need to boost the MIC signal. A single rail op-amp will do the job.

Did you already know which mic model you will use?

[scaenix]

Well, I'm hacking an old earphone to be used as mic, which, correct me if I'm wrong, makes it a unidirectional mic. I've tried the mic on an stereo amplifier and worked though. Sir, isn't the signal coming from the mic an analog signal? Please correct me again if I'm wrong.

[mister_e]

well any speaker/earphone could be more directional. But their sensitivity are usually pretty bad too. Never tried with any earphone (walkman or else).

What range of frequency you need to detect?

One thing is sure, you'll have to use a high pass filter to avoid any type of interference caused by your robot motor/floor/gear noise.

I really have to do something like that one day. As many other i've buyed the Robosapiens, dismantle it... and let him gathering dust

And yes the mic signal is analog.

PS: you don't need to call me sir. I'm not as old as Darrel Taylor is

[Darrel Taylor]

Hey, Hey now! I resemble that remark.

As many other i've buyed the Robosapiens, dismantle it... and let him gathering dust.

<table><tr><td align=center valign=top>What? Like this ...

</td><td><br><br><br>

Sitting on the shelf, next to my Teddy. </td></tr></table>

[scaenix]

well any speaker/earphone could be more directional. But their sensitivity are usually pretty bad too. Never tried with any earphone (walkman or else).

What range of frequency you need to detect?

One thing is sure, you'll have to use a high pass filter to avoid any type of interference caused by your robot motor/floor/gear noise.

I really have to do something like that one day. As many other i've buyed the Robosapiens, dismantle it... and let him gathering dust

And yes the mic signal is analog.

Apologies for calling you "sir"...

Hmm... I guess I should by a mic though. I need to detect frequencies above 15KHz. I'm bit pressured now 'coz the project I'm making is due next friday and I'm still in the design stage. Actually, this project was just thought out last January after realizing that our previous project proposal for our class is not going to materialize.