![](http://datasheet.mmic.net.cn/20000/MQ80C52CXXX-36SBR_datasheet_1389801/MQ80C52CXXX-36SBR_625.png)
625
6437E–ATARM–23-Apr-13
SAM9M11
33.7.8.12
Frame Slot Mode
This mode is useful only for Master nodes. It respects the following rule: each frame slot shall be
longer than or equal to TFrame_Maximum.
If the Frame Slot Mode is enabled (FSDIS = 0) and a frame transfer has been completed, the
TXRDY flag is set again only after TFrame_Maximum delay, from the start of frame. So the Mas-
ter node cannot send a new header if the frame slot duration of the previous frame is inferior to
TFrame_Maximum.
If the Frame Slot Mode is disabled (FDIS = 1) and a frame transfer has been completed, the
TXRDY flag is set again immediately.
The TFrame_Maximum is calculated as below:
If the Checksum is sent (CHKDIS = 0):
THeader_Nominal = 34 x TBit
TResponse_Nominal = 10 x (NData + 1) x TBit
TFrame_Maximum = 1.4 x (THeader_Nominal + TResponse_Nominal + 1)
(Note:) TFrame_Maximum = 1.4 x (34 + 10 x (DLC + 1 + 1) + 1) x TBIT
TFrame_Maximum = (77 + 14 x DLC) x TBIT
If the Checksum is not sent (CHKDIS = 1):
THeader_Nominal = 34 x TBit
TResponse_Nominal = 10 x NData x TBit
TFrame_Maximum = 1.4 x (THeader_Nominal + TResponse_Nominal +
1(Note:)) TFrame_Maximum = 1.4 x (34 + 10 x (DLC + 1) + 1) x TBIT
TFrame_Maximum = (63 + 14 x DLC) x TBIT
Note:
The term “+1” leads to an integer result for TFrame_Max (LIN Specification 1.3)
Figure 33-45. Frame Slot Mode
Break
Synch
Protected
Identifier
Data N
Checksum
Header
Inter-
frame
space
Response
space
Frame
Frame slot = TFrame_Maximum
Response
TXRDY
Write
US_THR
Write
US_LINID
Data 1
Data 2
Data 3
Data3
Data N-1
Data N
Frame Slot Mode
Disabled
Frame Slot Mode
Enabled
LINTC
Data 1