Datasheet

Section 20 Serial Communication Interface 3 (SCI3, IrDA)
REJ09B0465-0300 Rev. 3.00 Page 711 of 982
Sep 17, 2010
H8S/20103, H8S/20203, H8S/20223, H8S/20115, H8S/20215, H8S/20235 Group
20.4.5 Simultaneous Data Transmission and Reception
Figure 20.14 shows a sample flowchart for simultaneous transmit and receive operations. The
following procedure should be used for simultaneous data transmit and receive operations. To
switch from transmit mode to simultaneous transmit and receive mode, after checking that the
SCI3 has finished transmission and the TDRE and TEND flags are set to 1, clear TE to 0. Then
simultaneously set TE and RE to 1 with a single instruction. To switch from receive mode to
simultaneous transmit and receive mode, after checking that the SCI3 has finished reception, clear
RE to 0. Then after checking that the RDRF and receive error flags (OER, FER, and PER) are
cleared to 0, simultaneously set TE and RE to 1 with a single instruction.