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1  Topics / Home Automation and Networked Objects / Re: upload sketch to arduino via internet? on: October 17, 2011, 03:21:35 pm
The Mega 2560 should have enough memory if the standard Arduinos don't.

MarkT, afaik a running sketch cannot repleace itself unless it's the bootloader who does it but then again the bootloader might be to small to boot from the internet, maybe it could from the sd card wich would be fine for me, one could download the hex file to SD and then reboot.
2  Topics / Home Automation and Networked Objects / upload sketch to arduino via internet? on: October 17, 2011, 12:58:05 pm
did not find much on the web about this topic but think it's possible.

With 1 arduino it's hard/impossible to have enough memory to i/f the internet, program itself AND actually doing his real job.

How about using 2 arduinos, 1 to do the actual job and one that interfaces the internet and has an sd card i/f.

The internet arduino has 2 modes, 1-as internet to serial, 2- as programmer, both for the second arduino.

Send a hex file to the internet arduino who stores the file on the sd card, upon good reception it programs the second arduino.

Your objections/suggestion are very welcome.

3  Development / Other Hardware Development / Re: ATMEL Mega1284P evaluation board avalible on: August 17, 2011, 02:56:08 am
Well unless one stumbles on this topic nobody knows of the existance of this Mega1284P Bobuino board, maybe a mail to would draw the needed attention.
4  Development / Other Hardware Development / Re: ATMEL Mega1284P evaluation board avalible on: August 06, 2011, 04:33:53 am
hi, i'm erik and been following the great work in this topic for a while because this board is exactly what i need, please tell me how to buy a board.

5  Forum 2005-2010 (read only) / Development / Possible to use the ServoTimer1 library upto 360? on: January 08, 2009, 03:06:33 pm
I use 2 hitec HS-785HB sail(winch) servo's, the specs indicate they rotate 3.5 turns when normaly driven, normal servo's then do a 1/4 turn.
With the arduino ServoTimer1 library I can get upto 9 rotations, normal servo's get 1/2 turn.
Instead of an arm, my servo's have a gear that drives another gear, thus obtaining a 3 or 5x reduction and 3/5 x more power altough they are 3/5 x slower, it takes 15 seconds from one end to the other.

So I get more than 180 degrees, would it possible to modify the library to get 0-360 degrees? or even 360.0 degrees (using 3600 to avoid floating point math) to get higher precision?

I tried to replace all 180's to 360 in the library and the .h file but the servo goes crazy when I drive them over 180 degrees, what else should I modify?

Erik vdb
6  Forum 2005-2010 (read only) / Development / Re: 4MHz output from ports on: April 21, 2007, 02:49:08 am
neat trick but i think you get even higher frequenties when doing the loop in assembler code, look what asm can do.

7  Forum 2005-2010 (read only) / Development / Re: Arduino on the ATMEGA168 on: April 11, 2007, 04:13:48 am
still waiting for my 3 atmega168 to arrive from bigfun!

they arrived this morning!!!

thanks bigfun for the kind offer to return the money or send a new batch. excellent service.

8  Forum 2005-2010 (read only) / Bugs & Suggestions / Re: Arduino pin spacing on: March 23, 2007, 04:55:46 pm
i second that, i see no reason to repeat a mistake
9  Forum 2005-2010 (read only) / Interfacing / Re: any pga2310 volume control examples? on: March 19, 2009, 02:34:50 pm
Hi Bryan,
Nice to see you at the arduino forum, you might remember me from the panasonic forum (panoman aka Erik VDB, Belgium), we already emailed each other.

I see you just joined and already bought some stuff but I still want to point to some cheaper stuff not really/completely compatible with arduino.

this is a thai company producing many types of boards like:
and sell a RS232 arduino with ENC28J60 for $17 and mini boards also available via:

on request one can order their products via: search for ETT
I know these companies from my Thai holidays.

Here is a German company with an extreme low price:
pitty the arduino system does not run on the 32 and i'm not smart enough/to old to port it.

Succes with your new project,
10  Forum 2005-2010 (read only) / Interfacing / Re: ServoTimer2 - not standard on: January 23, 2009, 02:58:06 pm
Right mem,
the servo errors usually are pretty large and mostly due to the quality of the potmeter, especially the linearity, in a normal situation this is not noticed.
My servos are Hitec HS785HB and are actually winches used for sailing boat models and the rotate 1080 degrees (3.5 rotations) instead of the usual 90 degrees, this with standard 1000-2000us, with 592-2688 i get over 8 rotations.
this later reduced by 3 or 5 with the extra gear.
i can see almost every change by 1 us.
the pitch servo lifts the camera only from 0-180 degrees by supplying 1234-1792us, a difference of 558us, resulting in 0.32 degrees.
i would like to get a 1 degree but with right now i can be of by 0.16 degrees, with 0.5us precision this would only by a very acceptable 0,08 degrees.
the range of the yaw servo is 360 degrees so the error is doubled.

I understand that the precision is more than good enough in standard applications.
Could you point me out where modifications are needed in order to have the 0.5us drive?
11  Forum 2005-2010 (read only) / Interfacing / Re: ServoTimer2 - higher precision possible? on: January 23, 2009, 08:18:01 am
Hi mem,
I 'd like to use this library for driving my version of PanoDuino

In the function writeChan i notice that the actual precision is 0.5us

"servos[chan].counter = pulsewidth / 128;
servos[chan].remainder = 255 - (2 * (pulsewidth - ( servos[chan].counter * 128)));  // the number of 0.5us ticks for timer overflow"

Would it be possible to modify the library so that the pulsewidth can be given in 0.5us? like 2000 to 4000 or even a higher precision.

Also the "attach(pin, min, max  ) - Attaches to a pin setting min and max values in microseconds" is not implemented YET, are you planning to write this?
12  Forum 2005-2010 (read only) / Interfacing / Re: ServoTimer2 - drives up to 8 servos on: January 09, 2009, 10:27:21 am
I get these errors using this library
ServoTimer2.cpp: In constructor 'ServoTimer2::ServoTimer2()':
ServoTimer2.cpp:59: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:73: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:78: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:83: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:93: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:98: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:114: error: a function-definition is not allowed here before '{' token
ServoTimer2.cpp:132: error: expected `}' at end of input
ServoTimer2.cpp: At global scope:
ServoTimer2.cpp:10: warning: 'void initISR()' declared 'static' but never defined
ServoTimer2.cpp:11: warning: 'void writeChan(uint8_t, int)' declared 'static' but never defined
ServoTimer2.cpp:23: warning: 'isStarted' defined but not used

   if( ChannelCount < NBR_CHANNELS)
      this->chanIndex = ++ChannelCount;  // assign a channel number to this instance
      this->chanIndex = 0;  // todo      // too many channels, assigning 0 inhibits this instance from functioning

uint8_t ServoTimer2::attach(int pin)

How do I solve this?

13  Forum 2005-2010 (read only) / Interfacing / Re: Servo Library on: April 25, 2007, 11:14:08 am
As far as i know there is a standard that says:
1 ms = - 45 degrees
1.5 ms = 0
2 ms = + 45


- the feedback of a servo is done with a potmeter, correct me if i'm wrong but they have a tolerence of 10%.
- the joystick in the transmitter is made with potmeters having the same tolereance, each channel also has a trim, again a tolerance, to my knowledge there is a adjustment inside a good (analog, don't know about digital) zeroing out the errors of the transmitter.

This leaves us in the best case with a 10% error and worst case more than 20% but planes and cars have a mechanical trimming.
To compensate all this the servos travel more +-45 degrees some even go beyond +-90 degrees.

Notice that when you buy multiple 'identical' servos that each of them will be different in behavior, one cannot just replace a servo without trimming the plane,  car.... as the zero degrees position wil have shifted, there is no adjusment inside a servo.
Because in RC moddeling only +-45 degrees is used, the travel error wont be noticed, if one goes beyond specs as on this board most of us do, nothing is guarenteed.

I would propose that we search for the limits of each and every servo we use, trim the software and never exchange one servo with another to avoid retrimming of the software.

I hope this helps.


14  Forum 2005-2010 (read only) / Workshops / Re: panoramic tripod head using arduino on: June 20, 2009, 06:28:33 pm
sorry sync, but this way the npp (no parallax point, see does not stay in one place and thus creates parallax!

this is not a problem as long there are no objects near to the camera but it not fitted to do 360 by 180 (or Full Spherical, see: panoramas.

15  Forum 2005-2010 (read only) / Workshops / Re: panoramic tripod head using arduino on: June 19, 2009, 03:26:11 pm
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