Datasheet

Section 15 Serial Communication Interface (SCI)

Rev. 6.00 Mar. 18, 2010 Page 547 of 982

REJ09B0054-0600

Section 15 Serial Communication Interface (SCI)

This LSI has independent serial communication interfaces (SCIs). The SCI can handle both

asynchronous and clocked synchronous serial communication. Serial data communication can be

carried out using standard asynchronous communication chips such as a Universal Asynchronous

Receiver/Transmitter (UART) or an Asynchronous Communication Interface Adapter (ACIA). A

function is also provided for serial communication between processors (multiprocessor

communication function). The SCI also supports an IC card (Smart Card) interface conforming to

ISO/IEC 7816-3 (Identification Card) as a serial communication interface extended function.

15.1 Features

• The number of on-chip channels

H8S/2258 Group, H8S/2239 Group, H8S/2238 Group, and H8S/2237 Group: Four channels

(channels 0, 1, 2, and 3)

H8S/2227 Group: Three channels (channels 0, 1, and 3)

• Choice of asynchronous or clocked synchronous serial communication mode

• Full-duplex communication capability

The transmitter and receiver are mutually independent, enabling transmission and reception to

be executed simultaneously.

Double-buffering is used in both the transmitter and the receiver, enabling continuous

transmission and continuous reception of serial data.

• On-chip baud rate generator allows any bit rate to be selected

External clock can be selected as a transfer clock source (except for in Smart Card interface

mode).

• Choice of LSB-first or MSB-first transfer (except in the case of asynchronous mode 7-bit data)

• Four interrupt sources

Transmit-end, transmit-data-empty, receive-data-full, and receive error — that can issue

requests.

The transmit-data-empty interrupt and receive data full interrupts can be used to activate the

data transfer controller (DTC) or the direct memory access controller (DMAC) (H8S/2239

Group only).

• Module stop mode can be set

Asynchronous mode

• Data length: 7 or 8 bits

• Stop bit length: 1 or 2 bits