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NXP Semiconductors
UM191812
PN544 C2 User Manual
191812
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© NXP B.V. 2010. All rights reserved.
User Manual
Rev. 1.2 — 2010-06-16
23 of 172
Example of change baud rate LLC frame
(5) Change baud rate to 9600 (00h)
Fig 14. example of change baud rate LLC frame
7.4.4 CRC description
The detection of errors in a frame is based on the standard CRC-16 defined in [2]. The
CRC polynomial is:
X
16
+X
12
+ X
5
+1.
Its initial value is 0xFFFF.
The CRC is computed on the bits between SOF and EOF both excluded. So in order to
detect invalid frames the CRC shall be taken as a primary measure to check validity. The
maximum size of a single frame is (LEN+HDR+PAYLCRC = 1 + 1 + 29 + 2)
33 Bytes.
7.4.4.1 Example
The CRC of an RSET and an UA is as follows:
C3
F9
04
00
E5
05
CRC
Endpoint
Cap.
Window
size
RSET
Length
17
E6
A7
03
CRC
UA
Length
Fig 15. CRC examples