14.2.6 Serial Control Register (SCR)—H'FEDA, H'FEF2
The SCR is an 8-bit readable/writable register that enables or disables various SCI functions. It is
initialized to H'0C at a reset and in the standby modes.
Bit 7—Transmit Interrupt Enable (TIE):
This bit enables or disables the transmit-end interrupt
(TXI) requested when the transmit data register empty (TDRE) bit in the serial status register
(SSR) is set to 1.
Bit 7
TIE
0
1
Description
The transmit-end interrupt request (TXI) is disabled.
The transmit-end interrupt request (TXI) is enabled.
(Initial value)
Bit 6—Receive Interrupt Enable (RIE):
This bit enables or disables the receive-end interrupt
(RXI) requested when the receive data register full (RDRF) bit in the serial status register (SSR) is
set to 1. It also enables and disables the receive-error interrupt (ERI) request.
Bit 6
RIE
0
Description
The receive-end interrupt (RXI) and receive-error interrupt (ERI)
requests are disabled.
The receive-end interrupt (RXI) and receive-error interrupt (ERI) requests are enabled.
(Initial value)
1
Bit 5—Transmit Enable (TE):
This bit enables or disables the transmit function. When the
transmit function is enabled, the TXD pin is automatically used for output. When the transmit
function is disabled, the TXD pin can be used as a general-purpose I/O port.
Bit 5
TE
0
Description
The transmit function is disabled. The TXD pin can be
used as a general-purpose I/O port.
The transmit function is enabled. The TXD pin is used for output.
(Initial value)
1
Bit
7
6
5
4
3
2
1
0
TIE
RIE
TE
RE
—
—
CKE1
CKE0
Initial value
0
0
0
0
1
1
0
0
Read/Write
R/W
R/W
R/W
R/W
—
—
R/W
R/W
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