MBR =
0.9x VCLK
maxbaudrate
SCI/LIN Control Registers
1319
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Serial Communication Interface (SCI)/ Local Interconnect Network (LIN)
Module
25.13.30 Maximum Baud Rate Selection Register (MBRS)
and
illustrate this register.
Figure 25-58. Maximum Baud Rate Selection Register (MBRS) [offset = 7Ch]
31
16
Reserved
R-0
15
13
12
0
Reserved
MBR
R-0
R/WL-0DACh
LEGEND: R/W = Read/Write; R = Read only; WL = Write in LIN mode only; -
n
= value after reset
Table 25-46. Maximum Baud Rate Selection Register (MBRS) Field Descriptions
Bit
Field
Value
Description
31-13
Reserved
0
Reads return 0. Writes have no effect.
12-0
MBR
0-1FFFh
Maximum baud rate prescaler. This bit is effective in LIN mode only. This 13-bit prescaler is
used during the synchronization phase (see
) of a slave module if the ADAPT
bit is set. In this way, a SCI/LIN slave using an automatic or select bit rate modes detects any
LIN bus legal rate automatically.
The MBR value should be programmed to allow a maximum baud rate that is not more than
10% above the expected operating baud rate in the LIN network. Otherwise, a 0x00 data byte
could mistakenly be detected as a sync break.
The default value for a 70Mhz VCLK is 0xDAC.
This MBR prescaler is used by the wake-up and idle time counters for a constant expiration
time relative to a 20 kHz rate.
(52)