Ultrasonic Range Finder (95% done,need your 5%.;ref. inside)

[di@ne]

Hi guys, im currently doing a displayed ultrasonic range finder,i got my diagram from here,

https://www.electro-tech-online.com/custompdfs/2008/06/pic-sonar.pdf

A PIC sonar (ultrasonic) range finding project. (the main site)

I've finished breadboarding everything (triple checked it)
alas, nothig turned out on my display. (pic. attached)

I program my PIC with a generic PIC kit (pic. attached) with a given code from the site. But i think that i may have done something wrong in the programming part ( i just directly inputted the hex. file ) and im very bad at programming..If someone could tell me how should i 'properly' input the .hex file, i would be really happy.


i really apreciate your guys help.

 

[di@ne]

oh yeah, il send u guys a postcard from malaysia if i get my stuff working

 

[picbits]

Did you set the configuration bits correctly when you programmed it ?

If you haven't set the oscillator type/watchdog/etc etc in the config bits then it won't work properly (if at all).

 

[picbits]

Also, how are you powering it ? I see you have at least 4 cells. If you are driving the PIC with those without a voltage regulator and they are fresh cells then you are going to have more than 6 volts going into the PIC. This is out of spec and could damage the PIC.

If you are using a voltage regulator in the circuit then you might find that unless its a very low dropout regulator, you won't be getting 5 volts out of it unless you use at least 7-8 volts at its input.

 

[picbits]

And finally - are you sure your PIC is in the right place in that programming socket and the right orientation ?

 

[di@ne]

1. Dear Picbits, i am not sure how to set the configuration bits, is it possible to tell me more or send me a link where i can study more about it?

For the oscillator, i believe it has been set in 4Mhz the stock source code given where i just "simply" programmed it.
2.
A direct reading from my cell is going 4.78+- volts but from your suggestion i am going to fix a 5 V voltage regulator soon to prevent any complication.
I am not that experience,but i guess that my PIC is still
functioning properly since i still can erase and reprogrammed any given .hex

3. for the programming sockets, i followed the instruction from the data sheets given for an 18 pin (attached)..Is it any difference to programmed it with my socket model then a direct ICSP type programming from the diagram? and for the wiring orientation from my PIC to the display and others,i checked everything and it seems to be correct, i checked every pin from 1 to 18.


4. and for my ultrasonic (attached) im not sure how i connect it but i guess it is correct, is there any polarity where + - goes to?

thanks.

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on something else that is not related, for all of this problem i would ussually have an assistance from my course coordinator, but as you can see ( www.shienandy.com - Welcome ) ; i haven't have the chance to have a proper communication with him for a month since his gettting married and all other things his going thru...and basically i am doing most of the things with the help of people around me and the net.

 

[balinloughan]

Hi Di@ne,

Did you ever get this working? I'm trying to get teh same circuit working as well and having difficulties. Like you I just programmed the 16F88 with the supplied .hex file. I do see activity in the circuit - se attached scope shots. Only problem is that the range is only 10cm.

I have attached two scope shots - TX_pulses shows the 40Khz pulses from RB3. I think these look OK.
The second scope shot shows RB0 and RB3 when I have an object about 10cm from the sonars. If I go beyond 10cm the display's lsb just shows a random number and RB0 and RB3 look like attachment 1meter.png.

Any ideas as to what I have wrong? I have been over the circuit about 5 times and can't see any connection errors. I also used the .hex file as opposed to recompiling. I'm using the 16F88 as well. ..

I'm really lost and appreciate your help.