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31  Using Arduino / Microcontrollers / Re: SN74LS86 Pinout on: September 05, 2014, 08:01:36 am
Please VishalSubramanyam you are talking gibberish, the 86 is a quad logic gate that has nothing to do with SPI, nobody seems to know that USBasp is, you have not stated what processor you are using.

In short you are wasting everyone's time unless you can explain the problem and the hardware being used.

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Rob
32  Using Arduino / Project Guidance / Re: Arduino schematics for commercial use on: September 04, 2014, 09:23:53 pm
Quote
Selling or marketing an unapproved, non certified product, can result in FCC fines of up to $15,000 per devise.
For people like us who may just sell a few (or even a few 100) boards don't you get around this by calling it a "prototyping device" or some such.

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Rob
33  Using Arduino / Microcontrollers / Re: Arduino Due Clone on: September 04, 2014, 09:10:51 pm
I'm not an expert on the Due but AFAIK

1. don't know
2. don't know
3. no
4. yes, there is a built-in boot loader that will boot from the UART, if you can connect to that I think this will work. This is in fact what the 16U2 dose now on the Due. You will need to "press" the erase pin/button with a FET or some such.
5. yes, by connecting the USB cable to the Native USB port, there is a USB bootloader built in to the chip.

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Rob

34  Using Arduino / Microcontrollers / Re: Multiple external signals to an Arduino on: September 04, 2014, 09:04:09 pm
Depends a little on the amount of data, frequency of transmissions and what you mean by "process them", but should be able to, especially if you have an Arduino with 2 spare serial ports like the Mega.

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Rob
35  Using Arduino / Programming Questions / Re: Write once read many possibility? on: September 04, 2014, 08:56:05 pm
Quote
securely stored to the chip so a reader can read that specific data but nobody is able to tamper with it in any way.
When is this data to be stored? Statically at compile time or at run time?

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Rob
36  Using Arduino / Project Guidance / Re: can't receive data morethan 64byte on: September 04, 2014, 08:53:02 pm
Post your code.

But it sounds like you are filling the receive buffer (which quite by chance is 64 bytes in size) and not clearing the data in time so the remaining bytes are discarded.

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Rob
37  Using Arduino / Programming Questions / Re: Integers and Strings in the same serial message on: September 04, 2014, 06:00:57 pm
As has been mentioned above I don't see why you can't just send three bytes. The sending of stuff like "Fan 1" is a common beginner thing to do because they want the data to be human-readable, but computers don't care and it just makes life harder.

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Rob
38  Using Arduino / Microcontrollers / Re: Uploading code to multiple micro-controllers simultaniously on: September 04, 2014, 05:57:12 pm
How far apart are the chips? All on in the same box or spread out over a factory?

Unless in the same box (and maybe even then) I would provide off-line storage (say a small EEPROM/Flash chip) on each node and have the program read new code, check for errors, then save in the EEPROM. Then when all is downloaded and confirmed get each node to program itself from that EEPROM with a custom bootloader.


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Rob

39  Using Arduino / Networking, Protocols, and Devices / Re: CASE command working with manually typed character, but not BTserial character. on: September 04, 2014, 05:26:17 pm
From what I can see your transmitting code does this

Code:
   if((pinValues >> i) & 1)
            Serial.print("A");
 ...
    Serial.print("\r\n");

That's 3 bytes being sent, each about 1mS after the other. Then the receiving code does

Code:
   switch (inByte) {
    case 'A':   
      digitalWrite(13, HIGH);
      break;
   
    default:
      // turn all the LEDs off:

So the 'A" turns the LED on and 1mS later the '\r' turns it back off again because that's what every character except 'A' does due to the default case.

Or have I got the wrong end of the stick?

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Rob
40  Using Arduino / Networking, Protocols, and Devices / Re: read data from SPI on: September 04, 2014, 08:57:38 am
Does the SCK pin still work as GPIO when in SPI mode? If so you could toggle it once yourself with a couple of digitalWrites().

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Rob
41  Using Arduino / Networking, Protocols, and Devices / Re: CASE command working with manually typed character, but not BTserial character. on: September 03, 2014, 10:41:50 pm
What if you receive an 'A' and turn the LED on then 1mS later your received a '\r' and turn it off. Would you see that pulse?

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Rob
42  Using Arduino / Project Guidance / Re: Debugging on: September 03, 2014, 08:37:11 pm
Well actually it's not the LPCs as such as I think all ARMs have similar debugging capability. It's the the dev environment that makes the difference and the LPCXpresso boards have debugging built in, no ICE required just the standard USB cable and IDE.

The Due doesn't do that. IIRC there is a debug header but you need a separate ICE for that.

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Rob
43  Development / Other Software Development / Re: an easier way of working with arrays on: September 03, 2014, 06:51:12 pm
Quote
There's no check if you query things that are out of bounds, or simply allocated but not used.
Welcome to the world of C, the language that allows you to do anything including kill the machine smiley

Sure you can write a class that does all this, trouble is C is designed for memory-challenged CPUs and normally you can't afford the overhead for something like that.

This is slowly changing with all the 32-bit processors being released and I agree that faulty array indexing is a major cause of bugs.

Maybe there's a reason to have this in the same way that we have strings and the String class, one is bare metal and the other does neat stuff and is safer (I assume, I've never looked at the code). But as you have probably seen the String class is frowned upon around here. That said maybe that's just because it was unreliable (been fixed I think) and it's a resource hog.

Personally I miss some things from other languages like associative arrays, whether or not they are appropriate on a tiny embedded CPU is another story, but with the new CPUs maybe we can start getting a few goodies from higher-level languages.

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Rob
44  Using Arduino / Programming Questions / Re: EEPROM with Visi-Genie on: September 03, 2014, 06:35:57 pm
I don't think it can be made any simpler than cattledog's example, a 16-bit value is split into two bytes and written to EEPROM, then it's read back.

Have you even tried it out?


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Rob
45  Using Arduino / Project Guidance / Re: Arduino schematics for commercial use on: September 03, 2014, 06:29:35 pm
Even if you use the exact schematic your board design will be different and therefore radiate differently, so I would assume that certifications like FCC have to be done for your exact product, assuming of course they have to be done at all with a given country and product type.

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Rob
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