PI CHIP

[6666]

The UNIPI chip is not just for differential front ends .... here is a simple cut down "surf pi" front end .....

there are only 4 connections required from the front end to the UNIPI chip.

TX
Sample 1
Sample 2
ADC in.

For audio out just use a 1k resistor in series with 16 ohm headphones .... you will hear clicking like gieger counter with no target. Freq will increase with target.

moodz

[ATTACH]15952[/ATTACH]

Hi moodz
was this ever proven to be a working design ?
what type of "c" is on the output it says 10uF ?
which way should it go if its an elecro ?
thanks
6666

[moodz]

Hi moodz
was this ever proven to be a working design ?
what type of "c" is on the output it says 10uF ?
which way should it go if its an elecro ?
thanks
6666

Hi 6666 .. well its based on the surf PI .... which is a working design .. however it was more a demonstration of how to use the tx and sampling signals from the UNIPI chip.

The cap should be bipolar and you could even increase it to something like 220 uF since the signals we are passing here are very low frequency.

I would not call it a good design.

moodz.

[6666]

Thanks Moodz
cheers
6666

[moodz]

v300 UNIPI update

Version v300 now replaces v230 ( v230 only supported on dspic30f4012 ).

v300 uses the dspic30f4011 chip and provides 3 PWM and 4 sample pulse outputs as well as 4 press buttons , rotary encoder, serial interface ... yada yada.

The pulse drivers are now on board and tested and run off an independant supply ( upto +50 volts if required ) There are seven pulse drivers ( 3 pwm + 4 sample ). Each driver can be fed with a different voltage if required.

The code is currently under revision to support VLF detector mode and will be called the UNI-PIGSL ... by changing the frontend board you can swap between VLF and PI

The VLF frontend is being tested now.

happy new year ... moodz.

[6666]

Hi Moodz
thanks for the update on the V300
great work
just one thing is it possible to get the full size picture please
when i zoom in to see the details of the connections the picture breaks up

Happy new year to you to
6666

[Dr Vel]

Correct me if I am wrong but I think it is this diagram. Sorry about size Carl every time I try to shrink it the image is useless. Thanks Qiaozhi a very good idea, I removed it. Makes me crazy to have to scroll side to side to read a page, especially if I cause it. In lieu of image that was here, see the zip Qiaozhi posted below.

I notice everyone asks for hex files but is it possible Moodz can share the commented source? I realize He may be keeping it proprietary but if not it would be nice to be able to understand and experiment with the program.

[Qiaozhi]

Correct me if I am wrong but I think it is this diagram. Sorry about size Carl every time I try to shrink it the image is useless. I will not get upset if you delete this post.

In cases where the image is very large, but cannot be reduced in resolution without losing quality, post the file in either zip or rar format.

[hdphilip]

V300

is the v300 hex files posted somewhere? i can't seem to find them,

Philip

[moodz]

The V300 now updated to include an SPI port.

The SPI port is for bolting on the 24 bit ADC's and other goodies.

!!!!note two of the LCD control lines have moved See pins 35 and 37 on the 4011 !!!

Hex and schematic below.

moodz.

V300_20120203.zip

[6666]

Amazing Moodz
where did you get the Evaluation Board
cannot quite read the writing ?

cheers

[hdphilip]

hello Moodz,

thanks for the update, (i was inputing the design into eagle)

When i was breadboarding the CPU and display i noticed the LCD was inter-tied with the icsp witch was also sending the menu too.

One important item i noticed, after about ten minutes, the display would lock up, sense we're overclocking these chips, i increased the voltage to about 5.2 volts, which seemed to do the trick, the current draw was about 200ma, with the LCD on.

I see you added some buffer stages for the sample/pwm outputs, is your thinking along the lines of to provide some sort of isolation, and to eliminate the need for the mosfet drivers?

If you were to use the ADC on on the SPI line, would that free up some CPU overhead, and would it be best to mount ADC on the front end board?

[moodz]

Amazing Moodz
where did you get the Evaluation Board
cannot quite read the writing ?

cheers

My evaluation board is one of the chips soldered to an SSOP chip carrier

The factory evaluation board is quite pricey. ( about $160 I think )

moodz.

[moodz]

hello Moodz,

thanks for the update, (i was inputing the design into eagle)

When i was breadboarding the CPU and display i noticed the LCD was inter-tied with the icsp witch was also sending the menu too.

One important item i noticed, after about ten minutes, the display would lock up, sense we're overclocking these chips, i increased the voltage to about 5.2 volts, which seemed to do the trick, the current draw was about 200ma, with the LCD on.

I see you added some buffer stages for the sample/pwm outputs, is your thinking along the lines of to provide some sort of isolation, and to eliminate the need for the mosfet drivers?

If you were to use the ADC on on the SPI line, would that free up some CPU overhead, and would it be best to mount ADC on the front end board?

I did not need to increase the voltage to overclock these chips however any noise on the +5 logic supply will cause a lock up ..... could depend on your chip production version also .. they vary slightly. I will look into running the chip at half the current clock speed.

moodz

[moodz]

Here is a version of the 4011 code running at 20 MIPS instead of 40 MIPS .... the internal cpu clock is now 80 Mhz instead of 160 Mhz and well within the 120 Mhz manufacturer spec. I have not extensively checked the menus and timings so any feedback is welcome.

The current draw is now 115 mA ....

moodz.

UNIPI_4011_20MIPS_hex.zip

[hdphilip]

CPU speed

moodz,

I tried the 20MIPS code, i saw that you put 20MIPS on the second line to warn us on the slower speed

here's what i noticed (this was from my breadboard setup)

I also measured about 100 ma with the LCD display on.
At 5 volts worked fine.
The "update time" on the display seemed half as fast. (harder to read)

The 20MIPS software would be an excellent choice in troubleshooting,
when I programed it on my pickit 3, because of the lower operating current, i found the
pickit 3 was able to power the CPU and LCD . which the 40 MIPS software couldn't.

I'm using the 30 MIPS CPU.

we could use a switching regulator for the digital +5 volts, from our battery pack to help the overall efficiency.

faster the better!!

I reloaded the v300, the cpu is purring along at 5.2v , waiting for a PCB, when I get the PCB made i'll try the menu/ timing functions

Philip