4

e5530

4508B–RFID–02/02

Reading Distances

The e5530 is able to operate from very weak fields. Nevertheless, there are some

general rules which influence the achievable reading distance.

•

Best results are accomplished when the transponder points towards the reader coil.

•

The transponder should not be embedded in metal, which will reduce the applicable

magnetic field and thus the reading distance.

•

The strength of the generated magnetic field and the sensitivity of the demodulator

are the most important factors for a good reading distance.

Figure 6. Example for a 64-bit Code

The identification code is transmitted continously. After the RF field is applied, the

e5530H-232 starts with the first bit (MSB) of the header byte ’E6hex’ (’1110 0110’),

followed by a unique 56-bit serial number. No checksum is included in this sample code.

Pulsing the RF field may reduce the synchronization task as the first byte transmitted is

known already (i.e., E6hex). This is even feasible, if the first bit may be lost due to

reader synchronization problems.

Customer ID Code

Selection

In general the customer may choose any ID code suitable to his application. To avoid

code duplication, Atmel will define a fixed header – i.e, the first 8 bits of the code – for

each customer.

Modes of Operation –

Options

For any new product variant, the customer has to select the following operation options

which are configured in the laser ROM as well:

•

Bitrate, which is defined as field clocks per bit (e.g., RF/40 = 125 kHz/40 =

3.125 kBit/s) (see table Table 1 “Transmission Options”)

•

Modulation method (see Figure 5)

•

Code length: 32, 64, 96 or 128 bits

For programming the ID code into the laser ROM, one of the following data has to be

supplied:

•

ID code algorithm which is implemented in Atmel’s code management software

(Atmel will generate the codes as requested)

•

Customer generated ID codes on floppy disk or per email/ftp.

The format has to comply to the following rules:

–

The ID code file is a plain ASCII text file.

–

The code files should be compressed. Please make self extracting files.

–

The code files are used in alphabetical order of their file names (including

letters and numbers). Used - i.e. programmed - code files are discarded.

–

Each line of the code file must contain one ID code for one IC.

–

The code is in hexadecimal format. The code may contain spaces for better

readability.

E6

Header

56-bit ID code

00 00 00 10 2D 72 5D