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31  Forum 2005-2010 (read only) / Syntax & Programs / Re: Multiple serial bytes on: May 02, 2009, 11:13:08 pm
You can receive a string of characters over serial. Just use a character to initiate the conversation and another character as a terminator.

So if you wanted to send the string "John" you might send "0John9". Then tell your program if it receives a "0" expect more characters, then if it receives a "9" all the characters have been sent. This allows the characters to be received in the order they were intended.

There's quite a bit around the forum on the subject. Point is, it's very do'able, so you needn't worry that your flogging a dead horse .. or so to speak = )  
32  Forum 2005-2010 (read only) / Syntax & Programs / Re: C# communication help on: February 16, 2009, 04:47:53 am
Hunt around for a C# serial library, then talk to Arduino over usb.

Here's a c++ example

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1159335334/4#4

You might be able to re write it for c#
33  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: September 10, 2007, 09:08:21 pm
Nice one Loic, add it to the playground it would be a great benefit to others searching for RFID options. I think there's a variety of storage options, but I haven't got that far yet  ;D

I read something a while back about USB memory sticks or flash memory or something  smiley
34  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: September 07, 2007, 06:51:22 pm
Very nice, congrats!
35  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: September 03, 2007, 03:36:31 am
You should be able to use comma's to separate the tags:-

TextString myTags = TextString(5500); // enough for about 500 with comma's

myTags.setArray("1010101010,1010101011,1010101012,");

Then add a comma after the tag is scanned, and use:-

if (myTags.contains("1010101010,")) {
   // checks if myString contains the subString "1010101010,"
}

The 168 should hold over a thousand unique tags, not bad considering the readers ex China off eBay store 500 and cost about the same as an Arduino, but don't do all the cool stuff Arduino's can do.
36  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: September 02, 2007, 05:30:37 pm
ok, so that solved my problem.

Here's the revised code including the TextString library:-

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1185507207/30

I'm reading from 8 input switches, if one is pressed, then a reading is taken from the Parallax RFID. If a tag is recognized, all 8 LED's in the 3rd array of 8 LED's flashes. Otherwise, a LED corresponding to the switch pressed, is flashed.

So that's handy for when I need to demo a standalone version. Otherwise, the intent is to check valid tags against a database of tag's stored in a web based .txt file. That parts handled by processing/php so a connection is needed for it to operate (till I buy an Arduino BT).
37  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: September 02, 2007, 03:13:32 pm
That would be good. I need to compare the char variable that the tag is stored, against literals eg. "3300960185". It's not mission critical in my case, but the problems become a nag that I'd like to solve, and it would be nice to have a portable version.

My latest discoveries:-

http://www.arduino.cc/en/Tutorial/TextString

So I'll take a look at it this evening and see what it does.

Someone here also got 3 tags individually recognized, the english is broken, and I couldn't find any code.

http://www.sarades.no/index.php?paged=2
38  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: September 02, 2007, 12:41:07 am
I've got the same problem, in a round about kind of way. While, my tag checking will be handled outside Arduino, I'd still like a more portable version checking tags inside Arduino.

But, converting char to string I haven't found a means to do that yet, and have spent the better part of two days searching.
39  Forum 2005-2010 (read only) / Syntax & Programs / Re: rfid compare tag code on: August 29, 2007, 07:14:53 pm
Quote
Thank you kg4wsv,
I've been trying your suggestions for the last 24hours but with no success.

Ouch, I think most of us know that all too well.

Have you perhaps tried hacking this code:-

http://www.arduino.cc/playground/Learning/PRFID

It's for a parallax, but there might be something in it you could use.
40  Forum 2005-2010 (read only) / Syntax & Programs / Re: Memory on: February 04, 2009, 05:00:05 am
Quote
You can potentially put an interpreter and SD card file system code in the program memory, and connect up a 2Gbyte SD flash card to contain programs to be interpreted, but that's probably cheating, right?

I'd love to see a board with a 2gig SD card built in.. "SDuino"

I have a sketch thats max'ing out at around 600 lines of code. The "max out" is very subtle, parts of the program stop working.

This initially sent me on a false witch hunt, but after experimenting with removing one function at a time, I narrowed the issue down to DateTime.h, with EEPROM.h and wire.h, was too much for the 168.



41  Forum 2005-2010 (read only) / Syntax & Programs / Re: read sensor data while doing something else on: January 17, 2009, 03:55:37 am
A delay will stop execution, so eliminate the delays and replace them with counters.

Make the whole program one big loop, and if LED is flagged on, use the loop to countdown duration rather than delays = )
42  Forum 2005-2010 (read only) / Syntax & Programs / Re: Little Endian or Big Endian? on: December 01, 2008, 11:04:46 pm
Little. You can go to the main page www.arduino.cc and use the search box at the top of it, it gives better results than trying to use the forum search box = )
43  Forum 2005-2010 (read only) / Syntax & Programs / Re: Question abour EEPROM.write() on: November 23, 2008, 10:33:16 pm
The UPS, I think, is also explained at the bottom of the same post, eg, pin, capacitor and diode arrangement.

44  Forum 2005-2010 (read only) / Syntax & Programs / Re: Question abour EEPROM.write() on: November 23, 2008, 07:32:11 pm
Here's the post, spiffed did the testing - ignore the thread title he was testing EEPROM = )

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1214379954/21#21

45  Forum 2005-2010 (read only) / Syntax & Programs / Re: Question abour EEPROM.write() on: November 23, 2008, 07:27:13 pm
I just finished writing a simple FAT for EEPROM after reading the results of a test done by another member here, can't remember names sorry.

The tester got up to 3.2 million writes at one address - and the test only stopped after power ran out.

So the thought was, the specification 100,000 (per address) is at the extreme low end.

If you search EEPROM from the front page you'll probably find the results of the test.
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