SH7261 datasheet(917/1348 Pages) RENESAS

917 / 1348 page

Section 20 IEBus

TM Controller (IEB) [R5S72612] [R5S72613]

Rev. 2.00 Sep. 07, 2007 Page 885 of 1312

REJ09B0320-0200

(a)

Master Transmission

The master unit transmits the data bits and parity bit to the slave unit to write data from the master

unit to the slave unit. The slave unit receives the data bits and parity bit, and returns an

acknowledgement if the parity bit is even and the receive buffer is empty. If the parity bit is odd or

the receive buffer is not empty, the slave unit does not accept the corresponding data and does not

return an acknowledgement.

When the slave unit does not return an acknowledgement, the master unit retransmits the data.

This operation is repeated until either an acknowledgement from the slave unit is detected or the

maximum number of data transfer bytes is reached.

When the parity is even and the acknowledgement is output from the slave unit, the master unit

transmits the subsequent data if data remains and the maximum number of transfer bytes are not

exceeded.

In the case of broadcast communications, the slave unit does not return the acknowledgement, and

the master unit transfers data byte by byte.

(b)

Master Reception

The master unit outputs synchronous signals corresponding to all data bits to be read from the

slave unit.

The slave unit outputs the data bits and parity bit on the bus in accordance with the synchronous

signals from the master unit.

The master unit reads the parity bit output from the slave unit, and checks the parity. If the parity

is not even, or the receive buffer is not empty, the master unit rejects acceptance of the data, and

does not return the acknowledgement. The master unit reads the same data repeatedly if the

number of data does not exceed the maximum number of transfer bytes in one frame. If the parity

is even and the receive buffer is empty, the master unit accepts data and returns an

acknowledgement. The master unit reads in the subsequent data if the number of data does not

exceed the maximum number of transfer bytes in one frame.

SH7261 Datasheet(PDF) 917 Page - Renesas Technology Corp