Section 14 Serial Communication Interface (SCI)
Rev. 5.00 May 29, 2006 page 405 of 698
REJ09B0146-0500
In transmitting serial data, the SCI operates as follows:
1. The SCI monitors the TDRE bit in the SCSSR. When TDRE is cleared to 0 the SCI recognizes
that the SCTDR contains new data, and loads this data from the SCTDR into the SCTSR.
2. After loading the data from the SCTDR into the SCTSR, the SCI sets the TDRE bit to 1 and
starts transmitting. If the transmit-data-empty interrupt enable bit (TIE) in the SCSCR is set to
1, the SCI requests a transmit-data-empty interrupt (TXI) at this time. Serial transmit data is
transmitted in the following order from the TxD0 pin:
a. Start bit: One 0 bit is output.
b. Transmit data: Seven or eight bits are output, LSB first.
c. Multiprocessor bit: One multiprocessor bit (MPBT value) is output.
d. Stop bit: One or two 1 bits (stop bits) are output.
e. Marking: Output of 1 bits continues until the start bit of the next transmit data.
3. The SCI checks the TDRE bit when it outputs the stop bit. If TDRE is 0, the SCI loads data
from the SCTDR into the SCTSR, outputs the stop bit, then begins serial transmission of the
next frame. If TDRE is 1, the SCI sets the TEND bit in the SCSSR to 1, outputs the stop bit,
then continues output of 1 bits in the marking state. If the transmit-end interrupt enable bit
(TEIE) in the SCSCR is set to 1, a transmit-end interrupt (TEI) is requested at this time.
Figure 14.14 shows SCI transmission in the multiprocessor format.
Summary of Contents for SH7706 Series
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Page 160: ...Section 5 Cache Rev 5 00 May 29 2006 page 112 of 698 REJ09B0146 0500 ...
Page 370: ...Section 11 Watchdog Timer WDT Rev 5 00 May 29 2006 page 322 of 698 REJ09B0146 0500 ...
Page 554: ...Section 17 Pin Function Controller PFC Rev 5 00 May 29 2006 page 506 of 698 REJ09B0146 0500 ...
Page 576: ...Section 18 I O Ports Rev 5 00 May 29 2006 page 528 of 698 REJ09B0146 0500 ...
Page 746: ...Index Rev 5 00 May 29 2006 page 698 of 698 REJ09B0146 0500 ...
Page 749: ...SH7706 Group Hardware Manual ...