mlx90121 Melexis Company, mlx90121 Datasheet - Page 11

• Manufacturer Part Number: mlx90121
• Description: 13.56mhz Rfid Transceiver
• Manufacturer: Melexis Company

11.3.1.b. Direct Transmission
Before analog processing, data transmission can be either direct or pre-processed by means of hardware
accelerators. Direct transmission can be performed with the following setup:
Data has to be transmitted in real time by the microcontroller on DIN input. The modulation is done when
DIN is asserted low, so by default DIN has to be asserted high. If a configuration register has to be
written, keep DIN high when MODE is asserted low. In configuration mode, the field is held without
modulation independently of DIN.
11.3.1.c. Hardware Encoding Transmission
This programmable encoder allows predefining six different patterns of 8 bits. The encoder is selected by
setting the bit EncoderEn in the DigitalConfig register.
Symbol Setup
The six symbols are called EncoderSym0 to EncoderSym5. There is a seventh symbol which is hard-
coded to 0xFF (11111111).
A symbol is built with 8 bits as shown in the following figure.
ISO Examples
The ISO15693 protocol, mode 1 out of 4, is implemented using six symbols as shown in the following
table. Start of frame (SOF), end of frame (EOF) and pulses are all encoded using one symbol.
3901090121
Rev. 007
Symbol
Code
Page 11 of 26
1
0
1
1
13.56MHz RFID Transceiver
1
0
1
1
MLX90121
Data Sheet
Jan-2008