Fujitsu FR81S User Manual
CHAPTER 40: MULTI-FUNCTION SERIAL INTERFACE
7. Operation of LIN Interface (v2.1)
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : MULTI-FUNCTION SERIAL INTERFACE
FUJITSU SEMICONDUCTOR CONFIDENTIAL
269
7.3. Operation of Serial Timer
Operation of serial timer is shown.
The serial timer can be used for either of the timer function or the synchronous transmission function.
How to Start Serial Timer
There are three ways to start the serial timer: setting "1" to the serial timer enable bit (SACSR:TMRE),
starting by the external trigger, and starting by the Sync Field.
⋅
Start by using the serial timer enable bit (SACSR:TMRE)
When the external trigger enable bit (SACSR:TRGE) is set to "0" and the serial timer enable bit
(SACSR:TMRE) is set to "1", the serial timer starts and the serial timer register (STMR) starts counting
from 0.
Figure 7-16 Start by Using Serial Timer Enable Bit
(STMCR="10", SACSR:TRGE=TSYNE="0")
10
0
1
2
・・・
9
10
1
0
STMR
STMCR
TINT
TMRE
Serial timer activation
⋅
Start by External Trigger
When the external trigger enable bit (SACSR:TRGE) is set to "1", the serial timer starts and the serial
timer register (STMR) starts counting from 0 if an edge of the external trigger set by the trigger selection
bit (TRG1, 0) is detected while the serial timer enable bit (SACSR:TMRE) is "1".
Figure 7-17 Start by External Trigger
(STMCR="10", SACSR:TRGE="1", TSYNE=TRG1="0", TRG0="1")
10
0
1
2
・・・
9
10
1
0
STMR
STMCR
TINT
TMRE
External trigger
Serial timer activation
⋅
Start by Sync Field reception
When the serial timer is stopped and the auto baud rate adjustment bit (SACSR:AUTE) is "1", the serial
timer starts and the serial timer register (STMR) starts counting from 0 if LIN interface (v2.1) detects the
first falling edge of the Sync Field.
MB91520 Series
MN705-00010-1v0-E
1582