RfID with BS1-IC

ocon

Hello everybody,

I need some help here as I dont understand how the tags are stored into the EEPROM. If I run the sample program that displays the tag ID· (http://www.parallax.com/Portals/0/Downloads/src/prod/RFIDBasic1.zip) I get the ID as:

51 65 48 48 48 54 57 57 67 56

But if I store that number into the EEPROM with the other .bs1 example program (the one on http://www.parallax.com/Portals/0/Downloads/docs/cols/nv/vol6/col/nv120.pdf·) It says that the Tag is unknown.

I tried to convert it from decimal to HEX with a calc, but it wont work either. How can I use the tag ID's (or convert them if needed) in order to be used with my application?

Thank you all for your support,
Ocon

Tumbler

Hello Ocon,


Please post your second program here, so we can take a look at it.

·

Beau Schwabe

ocon,

The numbers reported back appear to be ASCII ... that's ok.. the conversion is different than what you would do for HEX.

ASCII to Decimal:

Rule #1) If the value is less than 58 subtract 48 and that is the decimal number.
Rule #2) If the value is greater than 64 subtract 64 and that is the place holder for the letter in the alphabet.

For example with your numbers....

51 - Apply Rule #1 - 3
65 - Apply Rule #2 - 1 -> A <- 1st letter in alphabet
48 - Apply Rule #1 - 0
48 - Apply Rule #1 - 0
48 - Apply Rule #1 - 0
54 - Apply Rule #1 - 6
57 - Apply Rule #1 - 9
57 - Apply Rule #1 - 9
67 - Apply Rule #2 - 3 -> C <- 3rd letter in alphabet
56 - Apply Rule #1 - 8

...So the value to place in EEPROM is ... 3A000699C8

EEPROM ("3A000699C8")

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Beau Schwabe

IC Layout Engineer
Parallax, Inc.

ocon

Thank you Beau,

I this seams to be the answer [noparse]:)[/noparse] I will try it in the next hours and let you know the outcome. I found this table to ease the conversion:

http://easycalculation.com/ascii-hex.php

Thank you again,
Ocon

Beau Schwabe (Parallax) said...
ocon,

The numbers reported back appear to be ASCII ... that's ok.. the conversion is different than what you would do for HEX.

ASCII to Decimal:

Rule #1) If the value is less than 58 subtract 48 and that is the decimal number.
Rule #2) If the value is greater than 64 subtract 64 and that is the place holder for the letter in the alphabet.

For example with your numbers....

51 - Apply Rule #1 - 3
65 - Apply Rule #2 - 1 -> A <- 1st letter in alphabet
48 - Apply Rule #1 - 0
48 - Apply Rule #1 - 0
48 - Apply Rule #1 - 0
54 - Apply Rule #1 - 6
57 - Apply Rule #1 - 9
57 - Apply Rule #1 - 9
67 - Apply Rule #2 - 3 -> C <- 3rd letter in alphabet
56 - Apply Rule #1 - 8

...So the value to place in EEPROM is ... 3A000699C8

EEPROM ("3A000699C8")