H8S2245 datasheet(504/818 Pages) RENESAS

504 / 818 page

Section 12 Serial Communication Interface (SCI)

Rev.3.00 Mar. 26, 2007 Page 462 of 772

REJ09B0355-0300

12.4

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 12.12 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 DTC to

perform data transfer. The TDRE flag is cleared to 0 automatically when data transfer is

performed by the DTC*. The 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 DTC to perform data transfer. The RDRF flag is cleared to 0 automatically when data

transfer is performed by the DTC*. The DTC cannot be activated by an ERI interrupt request.

Note: *

The flag is not cleared when DISEL is 0 and the transfer counter value is not 0.

H8S2245 Datasheet(PDF) 504 Page - Renesas Technology Corp