![](http://datasheet.mmic.net.cn/120000/SH7410_datasheet_3575231/SH7410_386.png)
364
Bit 3—Reserved. This bit is always read as 0. The write value should always be 0.
Bit 2—Transmit-End Interrupt Enable (TEIE): Enables the transmit-end interrupt (TEI). A TEI is
requested if the transmit data register (SCTDR) does not contain new transmit data when the most-
significant bit of the data in the transmit shift register (SCTSR) is transmitted.
Bit 2: TEIE
Description
0
Transmit-end interrupt (TEI) requests are disabled (initial value)
1
TEI requests are enabled
Note:
The TEI request can be cleared by reading the TDRE bit in the serial status register (SCSR)
after it has been set to 1, and then clearing TDRE to 0 and the transmit end (TEND) bit to 0;
or by clearing the TEIE bit to 0.
Bits 1–0—Clock Enables 1 and 0 (CKE1–CKE0): Select the SCI clock source and enable clock
output from the SCK pin. Depending on the combination of CKE1 and CKE0, the SCK pin can be
used as a serial clock output or serial clock input pin.
The CKE0 setting is valid only in asynchronous mode when the SCI is internally clocked
(CKE1 = 0). It is invalid in clock synchronous mode or during external clock operation
(CKI1 = 0). Always select the SCI operating mode in the serial mode register (SCMR) before
setting CKE1 and CKE0.
Bit 1:
CKE1
Bit 0:
CKE0 Transmission Mode
Description*
1
0
Asynchronous
Internal clock/SCK pin is input pin (input signal is
ignored)*
2
Clock synchronous
Internal clock/SCK pin outputs synchronous clock*
2
0
1
Asynchronous
Internal clock/SCK pin is clock output*
3
Clock synchronous
Internal clock/SCK pin is synchronous clock output
1
0
Asynchronous
External clock/SCK pin is clock input*
4
Clock synchronous
External clock/SCK pin is synchronous clock input
1
Asynchronous
External clock/SCK pin is clock input*
4
Clock synchronous
External clock/SCK pin is synchronous clock input
Notes: 1. The pin carrying the SCK signal is multiplexed with other functions. Use the pin function
controller (PFC) to set the pin for SCK functions.
2. Initial value.
3. Clock output that is same frequency as the bit rate.
4. Input of clock that is 16 times the bit rate.