Renesas H8S Family Hardware Manual page 597

Serial Pin Multiplexed Mode 4

(SMR0 Register [bits SM2, SM1, SM0] = [1 0 0])

Mode 4 provides the same function as mode 3, but the data lines of SCI_3 and SCIF are cross-

RxD1/TxD1 of SCI_1 are connected to Tx/Rx of COM1, and internal register bits emulate other

signals of COM1. DCD/RI/DSR/CTS of SCIF are fixed at 1. COM2 is not available (N/A) and Rx

for COM2 is fixed at 1. COM3 is not available (N/A) and Rx for COM3 is fixed at 1. RxD3/TxD3

of SCI_3 are cross-connected to TxDF/RxDF of SCIF internally.

The states of DCD/RI/DSR of COM1 are reflected in bits DCD1/RI1/DSR1 of the SMR0 register,

and CTS of COM1 is reflected to CTS1 bit of SMR1 register.

The values written to bits DTR1/RTS1 of the SMR1 register are output to DTR/RTS of COM1.

The value written to bit RTS3 of SMR1 is reflected in CTS of SCIF, and the state of RTS of SCIF

is reflected in bit CTS3 of SMR1, allowing SCI_3 and SCIF to communicate each other with

virtual flow control.

Figure 16.5 illustrates the pin connection in serial pin multiplexed mode 4.

Figure 16.5 Serial Pin Multiplexed Mode 4

Section 16 Serial Pin Multiplexed Modes

Rev. 1.00 Mar. 12, 2008 Page 549 of 1178

REJ09B0403-0100