CRX14_10 Datasheet, PDF (27/47 Pages) STMicroelectronics – ISO14443 type-B contactless coupler chip with anti-collision, CRC management and anti-clone function

CRX14
CRX14 ISO14443 type-B radio frequency data transfer
Figure 20. CRX14 request frame character format
b0 b1 b2 b3 b4 b5 b6 b7 b8 b9
1 Start _LSB
ETU '0'
Information Byte
MSB ^Stop
'1'
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Table 7.
Bit
CRX14 request frame character format
Description
b₀
Start bit used to synchronize the transmission
b₁ to b₈ Information Byte (instruction, address or data)
b₉
Stop bit used to indicate the end of the character
Value
b₀ = 0
Information Byte is sent Least
Significant Bit first
b₉ = 1
6.3
Request start of frame
The Start Of Frame (SOF) described in Figure 21 consists of:
● a falling edge,
● followed by ten Elementary Time Units (ETU) each containing a logical ‘0’
● followed by a single rising edge
● followed by two ETUs, each containing a logical ‘1’.
Figure 21. Request start of frame
b0 b1 b2 b3 b4 b5 b6 b7 b8 b9 b10 b11
ETU 0 0 0 0 0 0 0 0 0 0 1 1
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6.4
Request end of frame
The End Of Frame (EOF) shown in Figure 22 consists of:
● a falling edge,
● followed by ten Elementary Time Units (ETU) containing each a logical ‘0’,
● followed by a single rising edge.
Figure 22. Request end of frame
b0 b1 b2 b3 b4 b5 b6 b7 b8 b9
ETU 0
0
0
0
0
0
0
0
0
0
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Doc ID 8880 Rev 4
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