How to compare strings/array? RFID Project

[CSU_2010]

I'm trying to find out the RFID tag ID by reading the tag and displaying it on an LCD and I can't seem to figure it out. Has anyone else been able to display the tag ID on an LCD?

[ScaleRobotics]

I was at Radio Shack yesterday, trying to buy a breadboard. (No of course they didn't have it, why would my store have it in stock?)

Anyway, I was searching their bins and I saw a Parallax RFID READER WITH TAGS part number 276-0032, or this part: http://www.parallax.com/Store/Sensor...%2cProductName

It didn't have a price marked, so I had the lady scan it, and she told me it was $19.97. It's on my receipt as the correct part number, and correct product description. That's half off of Parallax's price, so if you are interested in RFID, you might want to check it out at Radio Shack.

[Ioannis]

At their site they do not list it though...

Ioannis

[RFEFX]

i thought id post it here.. since this thread helped in the trick math operation.

My Board runs a PIC16F877A @ 20Mhz

Video Here

define OSC 20
ADCON1=7
CMCON=7


LastTag         CON     3
X               VAR     byte
tagNum          VAR     byte                     ' from EEPROM table
idx             VAR     Byte                    ' tag byte index
char            VAR     Byte                    ' character from table
buf             var     byte(10)

'*****************************************************************

SYMBOL PWRLED = PORTB.2 'Software controlled power LED
SYMBOL RFID   = PORTC.5  'RFID /ENABLE


'*****************************************************************


Tag1 DATA  "0415146D53"  ' 2 cards registered...
Tag3 DATA  "30700D48A5" 


'*****************************************************************


HIGH PWRLED
HIGH RFID
PAUSE 1000

serout2 PORTC.0,84,[$55]      ' uOLED Initialize

'*****************************************************************

Reset:
gosub cls
PAUSE 1000

'*****************************************************************

Main:

  LOW rfid                                    ' activate the reader
    SERIN2 PORTC.4,396,[WAIT(10),str BUF\10]  ' wait for hdr + ID
  HIGH rfid                                   ' deactivate reader
 
Check_List:
FOR tagNum = 1 TO lasttag
FOR idx = 0 TO 9
READ (((tagNum - 1) * 10) + idx), char        'The Tricky Order of Operation
IF (char <> buf(idx)) THEN Bad_Char
NEXT
GOTO Tag_found
Bad_Char:
NEXT

Bad_tag:
FOR x = 1 TO 2
serout2 PORTC.0,84,[$73,$6,$4,$0,$F0," ACCESS",$00]  'cmd,column,row,font,Color(msb:lsb),“string”,$00
serout2 PORTC.0,84,[$73,$6,$8,$0,$F0," DENIED",$00]   
NEXT
PAUSE 4000
GOTO reset

Tag_Found:
for x = 0 to 2
serout2 PORTC.0,84,[$73,$6,$4,$0,$1F," ACCESS",$00]  'cmd,column,row,font,Color(msb:lsb),“string”,$00
serout2 PORTC.0,84,[$73,$6,$8,$0,$1F," GRANTED",$00]
next
pause 4000
GOTO reset


CLS:
FOR X = 0 TO 2
serout2 PORTC.0,84,[$45]
next
return

[Ioannis]

I wonder why you send the uOLED data 2 or 3 times in a loop.

Ioannis

[RFEFX]

In another post someone stated about lag issues with this particular uOLED from 4Dsystems They introduced Pauses, but i found out (through trial and error) that just sending the data a couple times in a loop (refreshing) rather than putting pauses in the the display code resolved any Lag issues. As you can see in the video it displays what im sending
to the display quite nicely and even before the RFID LED can change color.. I also dont read any ACK from the display, as it is not necessary and just slows down the process.

Cheers!

[Ioannis]

I see. OK, thanks.

What is you opinion about the display? (colors, brightness, sharpness).

Ioannis