Rainbow Electronics MAX66040 - Manual (Page 5)

MAX66040
ISO/IEC 14443 Type B-Compliant
Secure Memory
_______________________________________________________________________________________ 7
ISO/IEC 14443 Type B
Communication Concept
The communication between the master and the
MAX66040 (slave) is based on the exchange of data
packets. The master initiates every transaction; only
one side (master or slaves) transmits information at any
time. Data packets are composed of characters, which
always begin with a START bit and typically end with
one or more STOP bits (Figure 5). The least significant
data bit is transmitted first. Data characters have 8 bits.
Each data packet begins with a start-of-frame (SOF)
character and ends with an end-of-frame (EOF) charac-
ter. The EOF/SOF characters have 9 all-zero data bits
(Figure 6). The SOF has 2 STOP bits, after which data
characters are transmitted. A data packet with at least
3 bytes between SOF and EOF is called a frame
(Figure 7). The last two data characters of an
START
1
0
BIT 1 BIT 2 BIT 3 BIT 4 BIT 5 BIT 6 BIT 7 BIT 8
LSB MSB
STOP
Figure 5. ISO/IEC 14443 Data Character Format
ABRIDGED DATA SHEET