Skip to main content

Messages

This section allows you to view all Messages made by this member. Note that you can only see Messages made in areas you currently have access to.

Messages - dmmedia

1
Breakout boards / Re: MMA7455L free PCB built
Thanks Ian.
That's some Processing cube demo floating around the internet. I've just adapted it for BusPirate and fixed geometry.
Will share the source next week, when I get few minutes between work and sleep ;)
Also it is very pity, thet you have retired those PCBs. I wanted to solder another one, but now will have to etch my own and choose some other PCB :

Veda88, yes, it is not trivial, but possible, especially, if you have a hot air gun available.
Some guy do the soldering of these chips with the soldering iron, but I gave it up.
I've placed the PCB into mount, tinned it, then tinned the chip with soldering iron.
Then I placed the chip onto the PCB, started the hot air gun at 150 deg for preheating, then switched to 250 and carefully blowed over all sides. Touched the chip with a stick and it sat down. After that, I switched hot air gun to 100 deg and blowed the things during cooling down. At 100 degrees, I put my hot air gun away, waited few minutes for the PCB to cool down at all and soldered all other parts to it.
3
Project logs / Re: Bus Pirate 3.5 free PCB build
Yes, hand soldering with Weller WHS40D iron and flux cored solder of different gauges.
Actually solder mask helps a lot.
I do now apply solder mask to all my hand made PCBs and soldering became much easier.

Indeed, that is hard to see from the photo, the soldering near 4066 is pretty bad. There is a bug on PCB, which I wasn't aware of and it made me resoldering this chip several times before I have found the solution. There is a connection between two pins missing and it has to be patched by soldering a jumper out of piece of wire or bulk of solder.

Some time I'll make a reflow oven. I liked how it works, but I have no time for it now.
4
Project logs / Bus Pirate 3.5 free PCB build
Once upon a time I have received a mail from DangerousPrototypes.com

And when opened there was a free Bus Pirate PCB and a nice yellow visit card



That Bus Pirate PCB needed a couple of parts to get done



But when done, it became a shiny red handy tool



Self-checking the Bus Pirate and it turned out to be good



Thank you DangerousPrototypes team. It was an interesting experience with PIC microcontrollers. Can't wait for the next free PCB coupon. How do I get it? :)
5
Bus Pirate Development / Re: Homemade Bus Pirate
I am not Jozef, but I think I can help.

VS 2010 Express gave me an error also. I have directed to MS website, registered C# part of VS for free, got the serial, entered it and voila - no more errors. Perhaps you have the same error.

For the second question, I cannot remember the exact successful string, but the program should issue a couple of "poll..." strings after each block written and then should stop at the new empty line. Then you will know, that the processing stopped. If you have lots of repeating "poll..." strings, then something is wrong in your wiring between AVR and PIC.
7
Bus Pirate Development / Re: Homemade Bus Pirate
Sadly could not get it work with Arduino.

But, I have managed to make my Atmega16 work stable at 3,3V and at 1MHz internal oscillator and 4800 baud rate.
Changed the settings in AVR Studio, compiled programmer firmware and it worked.
A bit fiddling with your C# GUI program (at first did not noticed, that it programs block by block and interrupted it after 1st block programmed :D ), and now I have working Bus Pirate!
However selftest showed, that I have soldered ADC1 and ADC2 pins together. Will fix that soon and post a photo to get the next free PCB :)

Thanks a lot Jozef for your help.
8
Bus Pirate Development / Re: Homemade Bus Pirate
Thanks for update, Jozef

Circuit was very clear with your description. I have drawn it exactly as in your update. Only few values were uncertain.

That's interesting how Atmega8 works from 3.3V at 16MHz.
According to specs it shouldn't :) That's why there were my questions, but if it possible to push limits that much, then it may be useful.

Quote from specs:

• Operating Voltages
– 2.7V - 5.5V (ATmega8L)
– 4.5V - 5.5V (ATmega8)
• Speed Grades
– 0 - 8MHz (ATmega8L)
– 0 - 16MHz (ATmega8)

Unfortunately, it happened that I have no Atmega8 chips and my Atmega16 wouldn't work stable at 3.3V. So I will try to update the code and schematics for Arduino and will share it also if it work.
9
Bus Pirate Development / Re: Homemade Bus Pirate
Thank you very much for sharing, Jozef!

Just to be sure:
1. Atmega8 VCC = +5V? Wouldn't it be wise to use voltage level convertor to 3.3V then? (According to specs, PIC24 tolerates 5V on digital pins, but requires 3.3V on MCLR pin)
2. Button connected to GND?
3. green wire from pin 1 (RST) just forgotten and doesn't play?
4. XTAL is 16.0 and connected with capacitors of 18pF each?
5. Value of pin15 (PORTB1) to ICSP PGD resistor is 15K?
6. And there is no more hidden connections from ICSP pins?
11
Bus Pirate Development / Re: AVR based PIC programmer
Yes, exactly the same problem. Free PCB built Bus Pirate waits until I manage to get or do the PIC programmer and I thought about some JDM-like circuit through the FT232 convertor IC, but AVR based programmer would save a lot of time, since I have already an Arduino and several AVR chips as well. Please, share your work, if you have such an intention.