HD6432633 Datasheet, PDF (810/1453 Pages) Renesas Technology Corp – Series of Microcomputers (MCUs: microcomputer units)

16.4 SCI Interrupts
The SCI has four interrupt sources: the transmit-end interrupt (TEI) request, receive-error interrupt
(ERI) request, receive-data-full interrupt (RXI) request, and transmit-data-empty interrupt (TXI)
request. Table 16-13 shows the interrupt sources and their relative priorities. Individual interrupt
sources can be enabled or disabled with the TIE, RIE, and TEIE bits in the SCR. Each kind of
interrupt request is sent to the interrupt controller independently.
When the TDRE flag in SSR is set to 1, a TXI interrupt request is generated. When the TEND flag
in SSR is set to 1, a TEI interrupt request is generated. A TXI interrupt can activate the DMAC*
or DTC* to perform data transfer. The TDRE flag is cleared to 0 automatically when data transfer
is performed by the DMAC* or DTC*. The DMAC* or DTC* cannot be activated by a TEI
interrupt request.
When the RDRF flag in SSR is set to 1, an RXI interrupt request is generated. When the ORER,
PER, or FER flag in SSR is set to 1, an ERI interrupt request is generated. An RXI interrupt can
activate the DMAC* or DTC* to perform data transfer. The RDRF flag is cleared to 0
automatically when data transfer is performed by the DMAC* or DTC*. The DMAC* or DTC*
cannot be activated by an ERI interrupt request.
Note that the DMAC* cannot be activated by interrupts of SCI channels 2 to 4.
Note: * DMAC and DTC functions are not available in the H8S/2695.
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