Datasheet

Rev.6.00 Oct.28.2004 page 494 of 1016
REJ09B0138-0600H
[b] Transmit data:
8-bit or 7-bit data is output in LSB-first order.
[c] Parity bit or multiprocessor bit:
One parity bit (even or odd parity), or one multiprocessor bit is output.
A format in which neither a parity bit nor a multiprocessor bit is output can also be selected.
[d] Stop bit(s):
One or two 1-bits (stop bits) are output.
[e] Mark state:
1 is output continuously until the start bit that starts the next transmission is sent.
[3] The SCI checks the TDRE flag at the timing for sending the stop bit.
If the TDRE flag is cleared to 0, the data is transferred from TDR to TSR, the stop bit is sent, and then serial
transmission of the next frame is started.
If the TDRE flag is set to 1, the TEND flag in SSR is set to 1, the stop bit is sent, and then the “mark state” is entered
in which 1 is output continuously. If the TEIE bit in SCR is set to 1 at this time, a TEI interrupt request is generated.
Figure 14-6 shows an example of the operation for transmission in asynchronous mode.
TDRE
TEND
0
1 frame
D0 D1 D7 0/1 1 0 D0 D1 D7 0/1 1
1 1
DataStart
bit
Parity
bit
Stop
bit
Start
bit
Data Parity
bit
Stop
bit
TXI interrupt
request generated
Data written to TDR and
TDRE flag cleared to 0 in
TXI interrupt service routine
TEI interrupt
request generated
Idle state
(mark state)
TXI interrupt
request generated
Figure 14-6 Example of Operation in Transmission in Asynchronous Mode
(Example with 8-Bit Data, Parity, One Stop Bit)