Toshiba TMP92CM22FG TLCS-900/H1 Series Manual page 168

(4) Mode 3 (9-bit UART mode)
9-bit UART mode is selected by setting SC0MOD0<SM1:0> to 11. In this mode parity
bit cannot be added.
In the case of transmission the MSB (9th bit) is programmed to SC0MOD0<TB8>. In
the case of receiving it is stored in SC0CR<RB8>. When the buffer is written and read,
the MSB is read or written first, before the rest of the SC0BUF data.
Wakeup function
In 9-bit UART mode, the wakeup function for slave controllers is enabled by setting
SC0MOD0<WU> to 1. The interrupt INTRX0 occurs only when <RB8> = 1.
TXD RXD TXD
Master
Note: The TXD pin of each slave controller must be in open-drain output mode.
Figure 3.9.23 Serial Link Using Wakeup Function
RXD TXD
Slave 1 Slave 2
92CM22-166
RXD TXD RXD
Slave 3
TMP92CM22
2007-02-16