DEMOKITCRX14 STMicroelectronics, DEMOKITCRX14 Datasheet - Page 24

• Manufacturer Part Number: DEMOKITCRX14
• Description: RFID EVALUATION KIT ISO14443-B
• Manufacturer: STMicroelectronics
• Type: Development kitr

Specifications of DEMOKITCRX14

• Contents: CD-ROM, CRX14 Board, USB Transceiver, Samples and Documentation
• Processor To Be Evaluated: CRX14
• Interface Type: I2C
• Operating Supply Voltage: 5 V
• For Use With/related Products: CRX14
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 497-3704

Applying the I²C protocol to the CRX14 registers
Figure 15. CRX14-to-host transfer: I²C current address read from I/O frame register
5.3
5.4
24/47
Bus Master
CRX14 Write
Bus Slave
for ISO14443B
I²C authenticate register protocol
For information please contact your nearest STMicroelectronics sales office.
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 CRX14. If the I²C Host tries
to read the Slot Marker Register, the CRX14 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-CRX14 transfer: I²C write to slot marker register
S
T
A
R
T
1 0 1 0 XX X
Device
Select
Code
CRX14 Write
Bus Master
Bus Slave
R/W
ACK
Frame Length
Received
Figure 16
N
S
T
A
R
T
ACK
1 0 1 0 X X X
Device Select
Answer Frame
Doc ID 8880 Rev 4
for a description of the command).
Code
Data 1
Data
ACK
R/W
Answer Frame
ACK
Data 2
Data
Slot Marker
Register
Address
03h
ACK
Answer Frame
Data
ACK
S
T
O
P
ACK
Answer Frame
Data N
Data
NoACK
S
T
O
P
ai09246
CRX14
ai09245