SH7020 Datasheet, PDF (365/509 Pages) Renesas Technology Corp – SuperH™ RISC engine

• Bit 2 (transmit-end interrupt enable (TEIE)): TEIE enables or disables the transmit-end
interrupt (TEI) requested if TDR does not contain new transmit data when the MSB is
transmitted.
Bit 2: TEIE
0
1
Description
Transmit-end interrupt (TEI) requests are disabled* (initial value)
The TEI request can be cleared by reading the TDRE bit in the serial
status register (SSR) after it has been set to 1, then clearing TDRE to
0; by clearing the transmit end (TEND) bit to 0; or by clearing the TEIE
bit to 0.
Transmit-end interrupt (TEI) requests are enabled.
• Bits 1 and 0 (clock enable 1 and 0 (CKE1 and CKE0)): CKE1 and CKE0 select the SCI clock
source and enable or disable clock output from the SCK pin. Depending on the combination of
CKE1 and CKE0, the SCK pin can be used for general-purpose input/output, serial clock
output, or serial clock input.
The CKE0 setting is valid only in the asynchronous mode, and only when the SCI is internally
clocked (CKE1 = 0). The CKE0 setting is ignored in the clocked synchronous mode, or when
an external clock source is selected (CKE1 = 1). Select the SCI operating mode in the serial
mode register (SMR) before setting CKE1 and CKE0. For further details on selection of the
SCI clock source, see table 13.9 in section 13.3, Operation.
Bit 1: Bit 0:
CKE1 CKE0 Description*¹
0
0
Synchronous mode
Internal clock, SCK pin used for input pin (input
signal is ignored or output pin output level is
undefined)
Clocked synchronous mode Internal clock, SCK pin used for serial clock output*²
0
1
Synchronous mode
Internal clock, SCK pin used for clock output*³
Clocked synchronous mode Internal clock, SCK pin used for serial clock output
1
0
Synchronous mode
External clock, SCK pin used for clock input*⁴
Clocked synchronous mode External clock, SCK pin used for serial clock input
1
1
Synchronous mode
External clock, SCK pin used for clock input*⁴
Clocked synchronous mode External clock, SCK pin used for serial clock input
Notes: 1. The SCK pin is multiplexed with other functions. Set the pin function controller (PFC) to
select the SCK function and the SCK input/output of the SCK pin.
2. Initial value
3. The output clock frequency is the same as the bit rate.
4. The input clock frequency is 16 times the bit rate.
RENESAS 350