CR14-MQP STMicroelectronics, CR14-MQP Datasheet - Page 24

• Manufacturer Part Number: CR14-MQP
• Manufacturer: STMicroelectronics

Specifications of CR14-MQP

• Pin Count: 16
• Screening Level: Commercial
• Lead Free Status / Rohs Status: Compliant

Applying the I²C protocol to the CR14 registers
Figure 15. CR14-to-host transfer: I²C current address read from I/O frame register for ISO14443B
5.3
Figure 17. CR14-to-host transfer: I²C random address read from slot marker register
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CR14 Read
Bus Master
Bus Master
Bus Slave
Bus Slave
CR14 Write
I²C slot marker register protocol
An I²C Write command to the Slot Marker Register generates an automated sixteen-
command loop (See
All the answers from the ST short range memory devices that are detected, are written in
the Input/Output Frame Register.
Read from the I²C Slot Marker Register is not supported by the CR14. If the I²C Host tries to
read the Slot Marker Register, the CR14 will return the data value FFh in both Random
Address and Current Address Read modes until NoACK is generated by the I²C Host.
The result of the detection sequence is stored in the Input/Output Frame Register. This
Register can be read by the host by using I²C Random Address Read.
Figure 16. Host-to-CR14 transfer: I²C write to slot marker register
S
T
A
R
T
S
T
A
R
T
1 0 1 0 XX X
1 0 1 0 X X X
Device
Select
Code
Device Select
Code
R/W
ACK
CR14 Write
Bus Master
Bus Slave
Frame Length
R/W
Received
Figure 16
ACK
N
ACK
Slot Marker
Register
Address
S
T
A
R
T
Doc ID 11922 Rev 2
Answer Frame
for a description of the command).
00h
1 0 1 0 X X X
Data 1
Data
Device Select
Code
ACK
ACK
Answer Frame
R
E
S
T
A
R
T
1 0 1 0 X X X
Data 2
R/W
Data
ACK
Device Select
Code
ACK
Slot Marker
Answer Frame
Register
Address
03h
Data
R/W
ACK
ACK
ACK
Answer Frame
S
T
O
P
FFh
Data N
Data
NoACK
NoACK
ai12044
ai12043
S
T
O
P
ai12045
CR14
S
T
O
P