CR14 STMicroelectronics, CR14 Datasheet - Page 25

• Manufacturer Part Number: CR14
• Description: Low Cost Iso14443 Type-b Contactless Coupler Chip With Anti-collision And Crc Management
• Manufacturer: STMicroelectronics

CR14
Figure 17. CR14-to-Host Transfer: I²C Random Address Read from Slot Marker Register
Figure 18. CR14-to-Host Transfer: I²C Current Address Read from Slot Marker Register
5.4
CR14 Read
Bus Master
Bus Slave
Addresses above Location 06h
In I²C Write mode, when the CR14 receives the 8-bit register address, and the address is above
location 06h, the device does not acknowledge (NoACK) and deselects itself from the bus. The
Serial Data line, SDA, stays at logic ‘1’ (pull-up resistor), and the I²C Host receives a NoACK
during the 9th bit time. The SDA line stays High until the STOP condition is issued.
In the I²C Current and Random Address Read modes, when the CR14 receives the 8-bit
register address, and the address is above location 06h, the device does not acknowledge the
Device Select Code after the START condition, and deselects itself from the bus.
S
T
A
R
T
CR14 Read
1 0 1 0 X X X
Bus Master
Bus Slave
Device Select
Code
S
T
A
R
T
R/W
ACK
1 0 1 0 X X X
Device Select
Code
Slot Marker
Register
Address
00h
R/W
ACK
ACK
R
E
S
T
A
R
T
1 0 1 0 X X X
5 Applying the I²C protocol to the CR14 registers
FFh
Device Select
Code
NoACK
R/W
S
T
O
P
ACK
FFh
ai12047
NoACK
ai12045
S
T
O
P
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