406
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
Ds
Transfer
frame n+1
Retransferred frame
nth transfer frame
RDRF
[1]
PER
[2]
[3]
[4]
Figure 12-8 Retransfer Operation in SCI Receive Mode
•
Retransfer operation when SCI is in transmit mode
Figure 12-9 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.
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
Ds
Transfer
frame n+1
Retransferred frame
nth transfer frame
TDRE
TEND
[6]
ERS
Transfer to TSR from TDR
[7]
[9]
[8]
Transfer to TSR from TDR
Transfer to TSR
from TDR
Figure 12-9 Retransfer Operation in SCI Transmit Mode