SH7052 Datasheet, PDF (474/919 Pages) Renesas Technology Corp – SuperHTM RISC engine

14.2.6 Serial Control Register (SCR)
The serial control register (SCR) operates the SCI transmitter/receiver, selects the serial clock
output in asynchronous mode, enables/disables interrupt requests, and selects the transmit/receive
clock source. The CPU can always read and write to SCR. SCR is initialized to H'00 by a power-
on reset, and in hardware standby mode. It is not initialized by a manual reset, and in software
standby mode.
Bit: 7
6
5
4
3
2
1
0
TIE
RIE
TE
RE MPIE TEIE CKE1 CKE0
Initial value: 0
0
0
0
0
0
0
0
R/W: R/W R/W R/W R/W R/W R/W R/W R/W
• Bit 7—Transmit Interrupt Enable (TIE): Enables or disables the transmit-data-empty interrupt
(TXI) requested when the transmit data register empty bit (TDRE) in the serial status register
(SSR) is set to 1 by transfer of serial transmit data from TDR to TSR.
Bit 7: TIE
0
1
Description
Transmit-data-empty interrupt request (TXI) is disabled (Initial value)
The TXI interrupt request can be cleared by reading TDRE after it has
been set to 1, then clearing TDRE to 0, or by clearing TIE to 0.
Transmit-data-empty interrupt request (TXI) is enabled
• Bit 6—Receive Interrupt Enable (RIE): Enables or disables the receive-data-full interrupt
(RXI) requested when the receive data register full bit (RDRF) in the serial status register
(SSR) is set to 1 by transfer of serial receive data from RSR to RDR. It also enables or disables
receive-error interrupt (ERI) requests.
Bit 6: RIE
0
1
Description
Receive-data-full interrupt (RXI) and receive-error interrupt (ERI)
requests are disabled
(Initial value)
RXI and ERI interrupt requests can be cleared by reading the RDRF
flag or error flag (FER, PER, or ORER) after it has been set to 1, then
clearing the flag to 0, or by clearing RIE to 0.
Receive-data-full interrupt (RXI) and receive-error interrupt (ERI)
requests are enabled
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