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1  Community / Products and Services / Re: How do you guys promote your Arduino kickstarter projects on: Today at 07:33:17 pm
My "Mega-DIP" breakout boards are in.  Got a stencil, will see if I can put one together this weekend, or will find out the pitch is too fine for us.
2  General Category / General Discussion / Re: kickstarter - what a crock! on: Today at 07:12:22 pm
I don't know how the 2560 breakout board made it into the thread earlier; I have 2560 Mega breakout boards ready - need to get one assembled.
Need to order crystals ...
3  General Category / General Discussion / Re: kickstarter - what a crock! on: Today at 12:51:44 pm
The other thing with the teensy uC is that it is a 3.3V part that can accept 5V signals. It's output is VDD - 0.5V, so for 3.3V thats 2.8V for a high output, 9mA source current and 2mA sink current when VDD = 3.3V per table 5.2.3 of MK20DX256VLY7 datasheet. And 100mA current limit for the chip.
So a good fast processor for some things, yet needs IO help for other things.
As with anything, the uC choice is just one of the tradeoffs in a project.
4  Using Arduino / Networking, Protocols, and Devices / Re: SPI Signal Ground on: Today at 12:40:40 pm
I would connect Arduino Gnd to the first board in the chain where SCK & MOSI go to.
5  Using Arduino / General Electronics / Re: Parallel Circuit - Ground Voltage Difference on: Today at 12:36:04 pm
That would be the ideal state.
Perhaps heavier ground wire is needed.
Or bring each ground from a PCB back to the power supply vs daisychaining it thru the boards.
6  Using Arduino / LEDs and Multiplexing / Re: 42x11 LED matrix on: Today at 12:15:46 pm
I prefer SPI.transfer for sending to shift registers.
I'm no software genius either, I tend to approach things from the hardware point of view.
You can put your message into an array and arrange it so that a byte, or two in your design, are sent out. Since you're using a current control output chip for the cathodes, blink without delay with added counter can be used to display a row at a time. I guess you're doing that in your interrupt routine.
Say your message is in a 48 byte array, with 6 letters going across. You have two time periods.  One is the multiplex time period, the other is the scroll period.
Every multiplex time period, you turn off the anodes, write the cathode data for the next row, and turn on the next anode.
Every scroll period, you move the pointer in the array to the next column of data.

Code:
column #s of the array, say 0 to 49 (can be hundreds of bytes long)
00000000001111111111222222222233333333334444444444
01234567890123456789012345678901234567890123456789
HooHoEEEEoLooooLooooOOOOo row 7  small o used for spaces here for clarity
HooHoEooooLooooLooooOooOo row 6  in reality the capital letters would be 1
HooHoEooooLooooLooooOooOo row 5  and the o's a 0
HooHoEooooLooooLooooOooOo row 4 
HHHHoEEEEoLooooLooooOooOo row 3  Just hard to think of the data horizontally.
HooHoEooooLooooLooooOooOo row 2  Much easier (for me) to picture each column
HooHoEooooLooooLooooOooOo row 1  as a byte of data.
HooHoEEEEoLLLLoLLLLoOOOOo row 0

0123456789abcdef  these show the current 16 columns being displayed
-0123456789abcdef  moving along as scroll time goes by
--0123456789abcdef 
---0123456789abcdef
----0123456789abcdef
-----0123456789abcdef
------0123456789abcdef
-------0123456789abcdef

So:
Time period m0 (multiplex 0) data for row0 columns 0-15 go out
Time period m1 (multiplex 1) data for row1 columns 0-15 go out
Time period m2 (multiplex 2) data for row2 columns 0-15 go out
Time period m3 (multiplex 3) data for row3 columns 0-15 go out
Time period m4 (multiplex 4) data for row4 columns 0-15 go out
Time period m5 (multiplex 5) data for row5 columns 0-15 go out
Time period m6 (multiplex 6) data for row6 columns 0-15 go out
Time period m7 (multiplex 7) data for row7 columns 0-15 go out
repeat:
Time period m0 (multiplex 0) data for row0 columns 0-15 go out
Time period m1 (multiplex 1) data for row1 columns 0-15 go out
etc.
Every 3mS, the next multiplex data goes out.

Then every 100mS, the data is shifted.
Columns 0-15,
100mS later, 1-16
100mS later, 2-17

etc. until sometime later, you get to the end, the data starts to wrap around:

35-49, 0
36-49, 0,1
37-49, 0,1,2
38-49, 0-4
etc.

Then the times when you're just waiting for 3mS to go by, or 100mS, other stuff can occurring - updating the array contents, responding to serial messages, button pushes, etc.

Desribe it like that, I can follow it easily, it's easy to see where the data is coming from, it's easy to see what's happening.
With 8 functions and each LED needing a whole byte to describe it, it's just too messy.
7  Using Arduino / LEDs and Multiplexing / Re: 42x11 LED matrix on: Today at 09:51:38 am
Convoluted as in you have 8 functions, and 64 bytes for a letter when they could be defined in just 8.  I just have a hard time following what your code is doing.
8  Using Arduino / General Electronics / Re: Best PCB degign for beginner. on: Today at 09:48:16 am
Having a Value for each part is nice for when the Parts List is Exported into a .txt file, and then imporded into excel for manipulation, adding digikey/mouser part numbers, etc.
9  Using Arduino / Project Guidance / Re: self-controlled power switch on: Today at 09:33:38 am
I believe so TomG, I can't open pololu from here to confirm (network issues it seems).
10  General Category / General Discussion / Re: kickstarter - what a crock! on: Today at 09:14:10 am
Pinout -  mine is the DIP package pinout, 1 to 1. I didn't look to see what his is.
My price is posted with the pics on my website
Quote
Modeled after the Solarbotics Ardweeny, but adapted to have the 1284P on wirewrap socket headers instead of sitting under a board and having to solder all the legs to something.  Killed your chip? Pop in a new one!
Header for offboard FTDI Module (can be right angle or vertical), "L" LED at the edge of the board. Cuttable traces for Vcc from FTDI, DTR from FTDI, and for the L LED if you don't want a light.
$21.25 plus $5.25 USPS shipping to US addresses; international shipping is usually more.
$7.50 extra for an FTDI module - the one I use has a micro USB connector.
paypal to cardinalflyer at comcast dot net.
Pretty much cost of parts plus couple bucks for the SMD assembly. Was quicker to just put the parts on than trying to find a nice neat way to kit them up.
I suppose if I wanted to go nuts and do a couple hundred up front the material price would come down some.
11  General Category / General Discussion / kickstarter - what a crock! on: Today at 01:48:11 am
This was just sent to me by member TimJ:

https://www.kickstarter.com/projects/663438947/mini-duino?ref=discovery

$10,000 for  a 1284 board project!  Clearly I am in the wrong business  smiley-eek-blue
I designed, bought parts, assembled and made available in about a months time a Repairable(!) 1284 system on a board - and it certainly didn't take $10K!



12  Using Arduino / Project Guidance / Re: self-controlled power switch on: Today at 01:31:51 am
Special? They're just low voltage schottky diodes.

"with the gate pulled to VCC with a resistor, "
"it provides power to the uC, which pulls the P-FET's gate low."

That violates the requirement to keep IO pins <= VCC +0.5V tho.
Need the transistor between IO and P-FET gate so that a gate pulled high does not leak current into the pin and "phantom power" the chip.
Making the pin High-Z should let the N-FET gate pull down keep the power off.

I'm working 2 designs at once (with 3 others pending!), think I'll dig up some FETs and try this before I get too far on this board's layout & routing.
Design-wise, I think I'm on the right track tho.
13  Using Arduino / General Electronics / Re: Best PCB degign for beginner. on: August 20, 2014, 03:55:17 pm
Right click the part, select Value, and enter LMxxxx whatever.
Same with the holes. Right click, Properties, enlarge them to meet the sizes needed for that signal type that you set up under Edit:Net Classes.
14  Using Arduino / Microcontrollers / Re: Upload hex file using bootloader on: August 20, 2014, 03:44:07 pm
Post once, have a little patience please.

Could be the bootloader only looks at USB port.  You may have to rewrite it to load via serial. Beyond my capability.  Check the 32U4 datasheet, under Memory Programming, see if it's possible.
15  Using Arduino / Installation & Troubleshooting / Re: Connecting UNO with Mobile phone, help on: August 20, 2014, 03:39:49 pm
Try a PM to Ni$hant in India forum, he's been doing a lot of stuff with phones.
Might be android based, can't hurt to ask.
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