570
32072H–AVR32–10/2012
AT32UC3A3
Figure 25-28. Header Reception
”Slave Node Configuration” on page 576
.
25.6.10.7
Slave Node Synchronization
Synchronization is only done by the slave. If the Sync byte is not 0x55, an Inconsistent Sync
Field error is generated, and the LIN Inconsistend Sync Field Error bit in CSR (CSR.LINISFE) is
set. An interrupt request is generated if the LINISFE bit in IMR is set. CSR.LINISFE is cleared by
writing a one to CR.RSTSTA. The time between falling edges is measured by a 19-bit counter,
driven by the sampling clock (see
).
Figure 25-29. Sync Field
The counter starts when the Sync field start bit is detected, and continues for eight bit periods.
The 16 most significant bits (counter value divided by 8) becomes the new clock divider
(BRGR.CD), and the three least significant bits (the remainder) becomes the new fractional part
(BRGR.FP).
Figure 25-30. Slave Node Synchronization
The synchronization accuracy depends on:
Break Field
13 dominant bits (at 0)
Break
Delimiter
1 recessive bit
(at 1)
Start
Bit
1
0
1
0
1
0
1
0
Stop
Bit
Start
Bit
ID0 ID1 ID2
ID4
ID3
ID6
ID5
ID7
Stop
Bit
Synch Byte = 0x55
Baud Rate
Clock
RXD
Write US_CR
With RSTSTA=1
US_LINIR
LINID
Start
bit
Stop
bit
Synch Field
8 Tbit
2 Tbit
2 Tbit
2 Tbit
2 Tbit
RXD
Baud Rate
Clock
LINIDRX
Synchro Counter
000_0011_0001_0110_1101
BRGR
Clcok Divider (CD)
0000_0110_0010_1101
BRGR
Fractional Part (FP)
101
Initial CD
Initial FP
Reset
Start
Bit
1
0
1
0
1
0
1
0
Stop
Bit
Start
Bit
ID0 ID1 ID2 ID3 ID4 ID5 ID6 ID7
Break Field
13 dominant bits (at 0)
Stop
Bit
Break
Delimiter
1 recessive bit
(at 1)
Synch Byte = 0x55
Summary of Contents for AT32UC3A3128
Page 61: ...61 32072H AVR32 10 2012 AT32UC3A3 PLLEN PLL Enable 0 PLL is disabled 1 PLL is enabled...
Page 592: ...592 32072H AVR32 10 2012 AT32UC3A3 Manchester Configuration Register on page 614...
Page 989: ...989 32072H AVR32 10 2012 AT32UC3A3 37 2 Package Drawings Figure 37 1 TFBGA 144 package drawing...
Page 991: ...991 32072H AVR32 10 2012 AT32UC3A3 Figure 37 3 VFBGA 100 package drawing...