Fujitsu MB96300 series Hardware Manual page 489

MB96300 Super Series Hardware Manual
Table 20.4-2 Bit function of the serial mode register (SMRn)
Bit name
bit5 OTO:
One-to-one external
clock selection bit
bit4 EXT:
External clock
selection bit
bit3 REST:
Restart of
transmission reload
counter bit
bit2 UPCL:
USART
programmable clear
bit (Software reset)
bit1 SCKE:
Serial clock output
enable
bit0 SOE:
Serial data output
enable bit
This bit sets an external clock directly to the LIN-USART's serial clock. This function
is used for operating mode 2 (synchronous) slave mode operation.
This bit executes internal or external clock source for the reload counter
If a 1 is written to this bit the reload counter is restarted. Writing 0 to it has no effect.
Reading from this bit always returns 0.
Writing a 1 to this bit resets LIN-USART immediately. The register settings are
preserved. Possible reception or transmission will cut off.
All flags (TDRE, RDRF, LBD, PE, ORE, FRE) are cleared and the Reception Data
Register (RDRn) contains 00
always returns 0.
LIN-USART reset should performed after disabling the reception and transmission
interrupt enable bits.
• This bit controls the serial clock I/O ports.
• When this bit is 0, SCKn pin operates as general purpose I/O port or serial clock
input pin. When this bit is 1 and no other peripheral resource uses this pin as output ,
the pin operates as serial clock output pin and outputs clock in operating mode 2
(synchronous).
Note:
When using SCKn pin as serial clock input (SCKE=0) pin, set the corresponding bit
of DDR as input port and set the corresponding bit of PIER = 1. Also, select external
clock (EXT = 1) using the external clock selection bit.
Reference:
When the SCKn pin is assigned to serial clock output (SCKE=1) and no other
peripheral resource uses this pin as output, it functions as the serial clock output pin
(SCKn) regardless of the status of general input-output ports.
• This bit enables or disables the output of serial data.
• When this bit is 0, SOTn pin operates as general purpose I/O pin. When this bit is
1and no other peripheral resource uses this pin as output, SOTn pin operates as serial
data output pin (SOT).
Reference:
When the output of serial data is enabled (SOE=1) and no other peripheral resource
uses this pin as output, SOTn pin functions as serial data output pin (SOT) regardless
of the status of general input-output ports.
Function
. Writing 0 to this bit has no effect. Reading from it
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CHAPTER 20 USART
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