Help to design a PCB for my PI design!

[1843]

Hi Qiaozhi,
There are some errors... please see the changes needed to apply:
http://www.geotech1.com/forums/showp...&postcount=159
Thanks a lot!

Unregistered,
Any op-amp can be tried. I would use two NE5534's at first.

u5 u7 opamp

u5 and u7 = ?ad797 ?ad844 ?lf347 ?ne5534 ? ? ? ? ?

[Qiaozhi]

PI-111 Version 2.0

As promised, here is the latest version of 1843's PI-111 detector:

[Qiaozhi]

Hello to all!

Whots new in this project?
Too many great ideas.
I hope not stop to make some super machine.

Regards!

Updated schematic and PCB coming soon...
The data has not been posted yet due to other commitments.

[miki73]

Hello to all!

Whots new in this project?
Too many great ideas.
I hope not stop to make some super machine.

Regards!

[1843]

Simply I used two separate grounds(digital and analog) both connected to the negative pole of battery.(They're used for the PCBs without ground plane).
If you're going to use ground plane, simply rename the -12V to 0V.

Thanks

[Qiaozhi]

Hi Qiaozhi,

The negative pin of battery is gnd(0V) in the new schematic. not -12V...
R23 should be ommited.
The PMOS is IRF9640.
Batt.setting, speaker and Backlight are changed as this.

Thanks

In your schematic you have -12V electrically connected to 0V. Are you saying that you want these separated, and only connected at the starpoint near where the battery connection is made, or are you saying that you just want to rename the -12V net to 0V? Please can you make this clearer.

I will change the NMOS to a PMOS (forgot to do that) and remove R23.

[1843]

Hi Qiaozhi,

The negative pin of battery is gnd(0V) in the new schematic. not -12V...
R23 should be ommited.
The PMOS is IRF9640.
Batt.setting, speaker and Backlight are changed as this.

Thanks

[Qiaozhi]

New schematic

Hi 1843,

Please find the updated schematic attached. Let me know if you spot any errors, before I modify the layout.

Note: There were a couple of mistakes in your posted schematics:

1. The 2 opamps were show with pin8 as +V, when it should be pin7.
2. C8 was connected upside down (wrong polarity).

[Mustafa]

Hi,
If your source code is in assembly language, it doesn't take to much time to disassemble a working code. But if it is written is C or other high level language, it takes some time to decompile it.
Attached examples are from ReAVR V3.2.0 and AvrStudio V4.16.

[1843]

Hi 1843,
Why not explain your algorithm now, your code will be disassembled anyway, much nicer if you can reveal yourself the methods…..or have you stepped on patents?

Thankyous & Regards

Disassemble?! Huh! If you have tons of time, you can do so. You are very sure of yourself!...anyway!

Most likely new files will be posted next weekend.

Hi 1843,
Why not explain your algorithm now, your code will be disassembled anyway, much nicer if you can reveal yourself the methods…..or have you stepped on patents?

Thankyous & Regards

[okantex]

ADC conversion time of atmega644 is varying between 565us and 260us.

total RX delay time is around 270us , so we wont have chance to get second sample from same curve .
anyhow , we can still do it by one sample ,cause frequency of detection will be higer than our swinging rate.

but still wonder why each step of software is 3,75us while counting for A

[okantex]

Originally Posted by okantex
lets say you got first sample at 10us ,can you say you can get second at 30th us.
Yes, I can.

Hi 1843 ,

excuse me again , I am trying to learn.........
lets say atmega's S&H cap captured first sample in 2,5us after you hold on related pin.
to get second sample ,first atmega has to analyse first sample and empty the S&H cap.
I dont know ,so get it as question ,does atmega own a second timer to count caps slope integral growts?if it has second timer ,there is no problem.
then I have second question ,how long will it take for the second timer to count it. what are possible max. and min. values?



and another question for Sisco ,
why A (1 count ) is 3,75us?
is not each step of software equal to 1/ 8.000.000 seconds?
3,75us is 30times mor than this value,can you explain me howto calculte?

btw is the software algoritm above all the thing you have to write for controllling the unit ,or just a part of it? is it possible for me to see all with start descriptions of chip.how do you program it ,by bascom avr??


regards all
Okantex

[1843]

lets say you got first sample at 10us ,can you say you can get second at 30th us.

Yes, I can.

Now the next step is to program an ATmega8 for this PI!

Unregistered,
Which schematic are you going to use...? Notice that the Hex file is for the previous schematic.

Qiaozhi is drawing a new schmatic (or maybe a new PCB layout).

Regards,
1843