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Messages - znanev

1
Flash_Destroyer EEPROM tester / Re: Flash destroyer PCB?
[quote author="octal"]
You have the 5 pins header (PICKit2) and you can plug as many buttons as you want.
[/quote]

How might I forget about the programming header ;) That's probably because I'm constantly plugging the programmer in and out... thanks for the reminder that the programming pins can be easily re-purposed :)

About the RTC chip - I'm not sure why you're thinking it's obsolete - this is one of the few I2C chips with FRAM memory and that was the purpose of getting it (RTC and 8KB memory in single package). Though I have to agree that the DS1307 is much more cheaper.
2
Flash_Destroyer EEPROM tester / Re: Flash destroyer PCB?
Hi octal,

after I destroyed the poor EEPROM chip, I pulled it out of the socket and now I have a MCP9801 and DS32C35 connected with wires to the board. So the destroyer has now much more amicable functions - serving as digital clock + thermometer. DS32C35 has integrated oscillator and can easily replace DS1307. So I haven't made any modifications to the PCB.

On a side note - any idea how to implement input interface to set the clock with only one button :)
3
Flash_Destroyer EEPROM tester / Re: Free PCB build + EEPROM written to death :)
Yeah, the room keeps this temperature all the summer, despite the fluctuations from 10 - 25 outside. Even during the winter it seldom falls below 18 inside (if I forget to turn the heating on :)

So it seems my electrical appliances are lucky - working at the specified temperature sweetspot ;-)
4
Flash_Destroyer EEPROM tester / Re: Free PCB build + EEPROM written to death :)
Ian,

I've got the free PCB only from the Free PCB Sunday about a year ago (6th June to be precise ;)

Most of the parts I already had in my junkbox, only the missing displays delayed the completion of this project.


The 11 million writes seems to be consistent at room temperature (it was around 25 degrees Celsius here all the time).
5
Flash_Destroyer EEPROM tester / Free PCB build + EEPROM written to death :)
I started building the Flash Destroyer after I received the free PCB, but I had to put the project on hold due to some other high priority tasks and lack of some of the parts :)

The most expensive parts of this project were the 7-segment displays. I had a lot of different 7-segment displays in my junkbox, but most of them are not single digit. I didn't want to spend about £1 a digit for Kingbright's displays, so I headed to eBay for a quick search. I found these for about £3 shipped for 10 displays:

http://www.ebay.co.uk/itm/NEW-10-X-0-56 ... 335bfba94c

The part number of these displays is SM42056-1K and according the datasheet they are suitable replacement. These displays are a little bit taller and wider then the Kingbright's, but eventually fitted nicely on the PCB :)

After the PCB was built, I plugged the poor 24AA01-I/P into the socket and turned the power on.

This picture I took the moment I turned the power on, but due to my slow reaction and the shutter lag, some 500 cycles elapsed in an instant:

[attachment=3]

Then I left the poor boy sitting there and counting, counting ...

After 13 days elapsed, the counter was still ticking and the EEPROM survived over 7 million writes. I wanted to capture the precious moment of the display showing all 7s, but again I had no luck:

[attachment=2]

Event though I put the camera in burst mode, the speed was not sufficient to capture the exact moment. The photo before this one captured 7777762.

Then again I left the destroyer doing its job.

After 19 days since the start, I found the poor EEPROM had died:

[attachment=1]

I'm not sure where I got the firmware source from, but it seems it was an older version, because after the 10 million writes the display didn't show a dot but reverted to all 0s again. So in fact the total number of the writes the chip survived was about 11.4 million.

[attachment=0]

After the EEPROM had died, I played a bit with the sources and made the display capable of showing all alhpa-numeric characters (some were not that readable, but it is hard to represent some letters with only 7 segments :)

Now I'm working on re-purposing the Flash Destroyer into a digital thermometer. I will post my success (if any) here soon.
6
DIY Life projects / Free PCB build
About a year ago I received a free PCB and assembled the circuit. Now it works nicely as mood lamp and I decided to share the result.

First, here is a photo of the circuit sitting in a plastic box from business cards:

[attachment=3]

The first version of the "LED pod" I built for proof of concept. It looks really ugly, but did its job:

[attachment=2]

The LEDs came originally in crystal clear packages, so I sanded them with some fine sandpaper in order to make them "diffused" to better blend the different colours. I used 4 Red, 4 Green and 4 Blue LEDs for this proof of concept board.

After a while I decided to make the LED pod a little bit brighter, so I bought from eBay some PCBs like this one:

[attachment=1]

This took me about half a day to build due to the time required to "diffuse" all 24 LEDs :)

From the proof of concept board I noticed the red colour is noticeably dimmer compared to the other two, so this time I just doubled the red LEDs and the new LED pod now contains 6 green, 6 blue and 12 red LEDs.

And here is how the finished mood lamp looks now:

[attachment=0]

The globe is from an Ikea lamp I bought cheaply (something like £5) and blends the LED colours nicely.
7
Bus Pirate Support / Re: Self test results
OK,

as promised earlier, here is my report :)

I changed the faulty 3.3V VREG with a new one from Microchip - TC1185-3.3VCT713. I run the self-test again and here are the results:


HiZ>~
Disconnect any devices
Connect (Vpu to +5V) and (ADC to +3.3V)
Space to continue
Ctrl
AUX OK
MODE LED OK
PULLUP H OK
PULLUP L OK
VREG OK
ADC and supply
5V(4.98) OK
VPU(5.01) OK
3.3V(3.32) OK
ADC(3.32) OK
Bus high
MOSI OK
CLK OK
MISO OK
CS OK
Bus Hi-Z 0
MOSI OK
CLK OK
MISO OK
CS OK
Bus Hi-Z 1
MOSI OK
CLK OK
MISO OK
CS OK
MODE and VREG LEDs should be on!
Any key to exit
Found 0 errors.

So thank you all for your kind advices which helped to identify and repair the failure. Now my Bus Pirate is ready again for new experiments ;)
8
Bus Pirate Support / Re: Re: Self test results
Thank you, Sjaak!

I measured the output directly on the voltage regulator pin and it was the same as that on the 3v3 pin - around 2.24V. So it is the vreg at fault, as you suggested. I will order a new one and report back the result once I replace it :)

Thanks,
Zdravko
9
Bus Pirate Support / Re: Re: Self test results
Thanks Ian,

I am not in a hurry at all. I'd like to try to repair it myself, because when I bought the Bus Pirate the self-test passed OK, so it is my fault definitely ;) I would just like some guidances how to identify if the VREG is broken or if some resistor or capacitor is blown. I think I can easily find replacement parts here in UK.

Cheers,
Zdravko
10
Bus Pirate Support / Re: Re: Self test results
Any idea how I can easily check what is broken in order to replace it? Yesterday I played with the same bridge chip and I powered it through the ICSP header (3.3V and GND) and everything went fine. What is the easiest way I could check with a multimeter what is wrong with the 3.3V regulator?

Many thanks,
Zdravko
11
Bus Pirate Support / Re: Self test results
[quote author="Sjaak"]... so have you tried to let it rest (disconnected) and tried again?[/quote]

Disconnected and reconnected several times, but no go. I also though I overloaded it as the VREG LED was a bit dim. But now it lights OK, just the voltage is around 2.24 instead of 3.3.
12
Bus Pirate Support / Re: Self test results
Hi all,

it seems I have somehow managed to burn the 3.3V regulator of my BusPirate.

I did nothing fancy really, just connected a UART to I2C bridge, which seemed to respond properly to the commands I issued. But when I measured the voltage of the chip's output pins to ground, I was something like 2.24V instead of 3V I expected. Then I measured the voltage of the 3.3V to GND directly on the BusPirate with nothing attached and it read 2.24V again... So I went through the SelfTest routine and unfortunately there are two FAILs:
Code: [Select]
HiZ> ~
Disconnect any devices
Connect (Vpu to +5V) and (ADC to +3.3V)
Press a key to start
Ctrl
AUX OK
MODE LED OK
PULLUP H OK
PULLUP H OK
VREG OK
ADC and supply5V(4.93) OK
VPU(4.93) OK
3.3V(2.25) FAIL
ADC(2.26) FAIL
Bus high
MOSI OK
CLK OK
MISO OK
CS OK
Bus Hi-Z 0
MOSI OK
CLK OK
MISO OK
CS OK
Bus Hi-Z 1
MOSI OK
CLK OK
MISO OK
CS OK
MODE and VREG LEDs should be on! Any key exits.

Any help would be much appreciated.

Thanks,
Zdravko
13
General discussion / Re: Forum migration
Congrats for the successful forum migration!

I like the general look and feel of the forum.

But in my opinion this layout is loosing about half of the screen estate on wide-screen monitors. Can this be configurable through the control panel? Also I couldn't find where I can choose another theme.

Cheers,
zdravko
14
Pirate PIC programmer / Re: New PIC programmer adapter
Nice looking! I'm following this thread with great interest, waiting from the time when I'll be able to buy this adapter from Seeed.

Ian, you'll drop a post here once the adapter exits the factory, won't you? :)
15
Pirate PIC programmer / Re: New PIC programmer adapter
[quote author="ian"]
It will be available eventually. I don't know the price, it's still in development, but under $20 or it's not worth it.  This PCB went out this week, it'll be back in a month to stuff and test. Then we have to write some software to support it :) It will be available fully assembled, and we can probably have boards made up if you like too.
[/quote]

Thanks for the explanation, Ian!

Hehe, it seems I'm too impatient ;)