HD6432351 datasheet(674/1025 Pages) RENESAS

674 / 1025 page

Section 14 Smart Card Interface

Rev. 3.00 Sep 15, 2006 page 640 of 988

REJ09B0330-0300

Retransfer operation when SCI is in transmit mode: Figure 14.12 illustrates the retransfer

operation when the SCI is in transmit mode.

[6] If an error signal is sent back from the receiving end after transmission of one frame is

completed, the ERS bit in SSR is set to 1. If the RIE bit in SCR is enabled at this time, an ERI

interrupt request is generated. The ERS bit in SSR should be kept cleared to 0 until the next

parity bit is sampled.

[7] The TEND bit in SSR is not set for a frame for which an error signal indicating an abnormality

is received.

[8] If an error signal is not sent back from the receiving end, the ERS bit in SSR is not set.

[9] If an error signal is not sent back from the receiving end, transmission of one frame, including

a retransfer, is judged to have been completed, and the TEND bit in SSR is set to 1. If the TIE

bit in SCR is enabled at this time, a TXI interrupt request is generated.

If data transfer by the DMAC or DTC by means of the TXI source is enabled, the next data can

be written to TDR automatically. When data is written to TDR by the DMAC or DTC, the

TDRE bit is automatically cleared to 0.

D0 D1 D2 D3 D4 D5 D6 D7 Dp DE

Ds D0 D1 D2 D3 D4 D5 D6 D7 Dp

(DE)

Ds D0 D1 D2 D3 D4

Transfer

frame n+1

Retransferred frame

nth transfer frame

TDRE

TEND

[6]

FER/ERS

Transfer to TSR from TDR

[7]

[9]

[8]

Transfer to TSR from TDR

Transfer to TSR

from TDR

Figure 14.12 Retransfer Operation in SCI Transmit Mode

HD6432351 Datasheet(PDF) 674 Page - Renesas Technology Corp