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1  Using Arduino / Project Guidance / Re: Need guidance: Measuring encoder position and sending data with Ethernet/WiFi on: December 09, 2013, 04:34:17 am
If the arduino can't keep up with the encoder count, you can use a dedicated chip (or the count function on the 32Bit Due) or use and FPGA like Pappilio which can run Arduino as well. As this is done in Parallel there should be no real issues there.
As for encoders, Absolute encoders gets expensive and all they really do is have a battery onboard that allows the count to be saved when the power goes off.
Just need to a home position for the encoder on power-up, thats all.

K
2  Using Arduino / Networking, Protocols, and Devices / Re: Auto Address Sensing on: November 28, 2013, 01:54:44 pm
I read that I2C is good for 20 to 30m with an I2C bus extender.

I read a bit about DMX, but don't see how this could be satify.

I would like the addresses to be set automatically, if feasible.
This way I can simply swap the slaves around and room_1 will always be room_1 no matter what slave I connect and without doing any addresssing apart from a power down/up.

The above may require that I run a another wire between each slave and each slave is initialiased in a set order, ie
when slave_1 is up and running and master has given it an address, the an output goes high to the Slave_2 which then get initilaised.

Feasible ?, I guess, but too complicated ?

K
                 
3  Using Arduino / Networking, Protocols, and Devices / Re: Auto Address Sensing on: November 27, 2013, 11:30:30 pm
Ha

Just stumpled across something about the I2C bus with a bus extender, it should be good for 20 to 30 meters.
Will investigate this......

K
4  Using Arduino / Networking, Protocols, and Devices / Auto Address Sensing on: November 27, 2013, 11:00:36 pm
Hi

I've got 8 slaves running from a master and would like to be able to have some sort of auto sensing.
Comminication is via RS485 and the slaves are approx 5 meters apart.

The slaves all does the same function and I/O's are the same.
So instead of manually set an address, I would like to be able to just plug the boards in and the master knows where the slave is.

So I figure that master talks to slave1 and slave1 talks to slave2 etc

I have looked around on the site for sample code but have't found any.
possible using the wrong seach terms, but I have tried a few name variations

Any suggestions ?

Kim
5  Development / Other Software Development / Re: eFLL (Embedded Fuzzy Logic Library) - Fuzzy Logic on Arduino on: September 22, 2013, 06:09:48 pm
Just stumbled across this.
Is anyone using this library and if yes, any comment ?

Thanks
6  Development / Other Hardware Development / Re: BLDC shield development suitable for Arduino due on: September 21, 2013, 05:00:51 am
I think that advanced position control, accel/decel rate, s curve smoothing with quadrature encoder feedback would be very useful.
Not sure if serial would be beneficial as could be done via the Arduino.

Nice work :-)
7  Using Arduino / Programming Questions / Re: dfrobot flame sensor coding on: August 29, 2013, 09:45:12 pm
Well, when using just one sensor the ambient light will have an effect.
One way is to add another sensor which is physically offset, ie 30 degrees, so you measure the difference and act when the difference is more than x
Off course you could also do this with one sensor, read the ambient light at the start, then act when it is more than x, just not as likely to be as reliable in real lift, but cheaper :-)

K
8  Using Arduino / Programming Questions / Re: clock-driven round robin scheduler on: June 02, 2013, 03:25:57 am
I just want to make sure that no tasks take longer than a set time and that I get back to some tasks within a specified time.

If the task overrun in time, I just need to set a semaphore so I know. Possible do some controlled shutdown or something.

Would be handy to know which task overflows, but at this point is properly not necessary.

I don't need priority, dynamic scheduling or anything like that.

Round Robin schedulers are predictable.
Trying to eliminate use of interrupts to get predictability

Was sure this most have been done numerous times, but maybe not released as free/w

Have been watching the TTE systems videos on youtube and like his approach, predictability :-)



9  Using Arduino / Programming Questions / clock-driven round robin scheduler on: June 01, 2013, 02:21:21 pm
Hi

Im looking for a clock-driven round robin scheduler for the Arduino
Just need an task overrun indicator

I have had look but they all appear to be or close fully blown RTOS's

Any suggestions

Ta
10  Using Arduino / Programming Questions / Re: Eclipse linux Jantje's plugin on: May 30, 2013, 07:34:49 pm
Are you sure Eclipse is pointing to the right directory structure
There might be more than one place

I haven't got Eclipse at work so I cant check.

If blink works, try to include the wire.h and work from there
11  Products / Arduino Due / Re: SerialUSB instability - Program stalls on: March 30, 2013, 03:20:23 am
I think your timer may have a hickup when rolling over to zero.

micros() should use a "unsigned long" and not a "double"

K
12  Using Arduino / Programming Questions / Quadrature Encoder Library on: February 12, 2013, 01:50:29 am
Does anyone know of a library that can read a quadrature encoder and can calculate speed, acceleration, declaration, position etc
Searched the net by found nothing yet

Ta
13  Products / Arduino Due / Re: Downloading to due from Ubunti 12.10 with arduino ide on: January 20, 2013, 07:22:36 pm
I ran Ubuntu fine, but is now running Mint (a Ubuntu derivative).
There is/was an issue occasionally with the USB drivers under Linux.
You may want to search for this in the Ubuntu forum.

Does the standard Arduino IDE run and download fine ?
14  Using Arduino / Networking, Protocols, and Devices / Re: Serial.write error when sending an array on: January 15, 2013, 03:24:58 am
Cheers for that.
Coming from a 8bit assembly world, C can be a bit hard to to interpret at time
int used to be a byte for me

getting there
:-)
15  Using Arduino / Networking, Protocols, and Devices / Serial.write error when sending an array on: January 15, 2013, 02:57:53 am
the following code has a compiler error, which I don't quite understand

Code:
int serialArrayOne[]  = {1,2,3,4,5,6,7,8};

void setup()
{
  Serial.begin(9600);
}

void loop()
{
  Serial.write(serialArrayOne,8);
}


error is:
sketch_jan15a.cpp: In function ‘void loop()’:
sketch_jan15a.cpp:19:32: error: no matching function for call to ‘HardwareSerial::write(int [8], int)’
/usr/share/arduino/hardware/arduino/cores/arduino/HardwareSerial.h:58:20: note: candidates are: virtual size_t HardwareSerial::write(uint8_t)
/usr/share/arduino/hardware/arduino/cores/arduino/Print.h:50:20: note:                 virtual size_t Print::write(const uint8_t*, size_t)
/usr/share/arduino/hardware/arduino/cores/arduino/Print.h:49:12: note:                 size_t Print::write(const char*)

The manual says
Serial.write(buf, len)
buf: an array to send as a series of bytes
len: the length of the buffer

Anyone care to enlighten me

Cheers
Kim
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