mfrc52301hn1-trayb NXP Semiconductors, mfrc52301hn1-trayb Datasheet - Page 17

• Manufacturer Part Number: mfrc52301hn1-trayb
• Description: Contactless Reader Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
MFRC523_33
Product data sheet
PUBLIC
8.3.4.1 Data validity
8.3.4.2 START and STOP conditions
8.3.4.3 Byte format
Data on the SDA line must be stable during the HIGH clock period. The HIGH or LOW
state of the data line must only change when the clock signal on SCL is LOW.
To manage the data transfer on the I
are defined.
The I
after the START condition. The bus is free again a certain time after the STOP condition.
The bus stays busy if a repeated START (Sr) is generated instead of a STOP condition.
The START (S) and repeated START (Sr) conditions are functionally identical. Therefore,
S is used as a generic term to represent both the START (S) and repeated START (Sr)
conditions.
Each byte must be followed by an acknowledge bit. Data is transferred with the MSB first;
see
but must meet the read/write cycle format.
Fig 12. Bit transfer on the I
Fig 13. START and STOP conditions
•
•
A START condition is defined with a HIGH-to-LOW transition on the SDA line while
SCL is HIGH.
A STOP condition is defined with a LOW-to-HIGH transition on the SDA line while
SCL is HIGH.
Figure
2
C-bus master always generates the START and STOP conditions. The bus is busy
SDA
SCL
16. The number of transmitted bytes during one data transfer is unrestricted
START condition
All information provided in this document is subject to legal disclaimers.
SDA
SCL
S
Rev. 3.3 — 5 March 2010
2
C-bus
115233
data valid
data line
stable;
2
C-bus, unique START (S) and STOP (P) conditions
change
allowed
of data
STOP condition
Contactless reader IC
mbc621
P
MFRC523
© NXP B.V. 2010. All rights reserved.
mbc622
SDA
SCL
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