TMP91C824
91C824-144
* Clock state
System clock: High frequency (fc)
Clock gear: 1 (fc)
Prescaler clock: System clock
Main settings
7 6 5 4 3 2 1 0
PCCR
←
−
−
− − − −
0
−
Set PC1 to function as the RXD0 pin.
SC0MOD
←
−
0 1 X 1 0 0 1
Enable receiving in 8-Bit UART Mode.
SC0CR
←
X 0 1 X X X 0 0
Add even parity.
BR0CR
←
0 0 0 1 0 1 0 1
Set the transfer rate to 9600 bps.
INTES0
←
−
−
− −
1 1 0 0
Enable the INTTX0 interrupt and set it to Interrupt Level 4.
Interrupt processing
Acc
←
SC0CR AND 00011100
if Acc
≠
0 then ERROR
Check for errors.
Acc
←
SC0BUF
Read the received data.
(note): X = Don’t care; “
−
” = No change
(4) Mode 3 (9-Bit UART Mode)
9-Bit UART Mode is selected by setting SC0MOD0<SM1, SM0> to 11. In this mode parity bit
cannot be added.
In the case of transmission the MSB (9th bit) is written 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.
Wake-up function
In 9-Bit UART Mode, the wake-up function for slave controllers is enabled by setting
SC0MOD0<WU> to 1. The interrupt INTRX0 occurs only when<RB8> = 1.
TXD
Master
Slave 1
Slave 2
Slave 3
RXD
TXD
RXD
TXD
TXD
RXD
RXD
(note): The TXD pin of each slave controller must be in Open-Drain Output Mode.
Figure 3.9.23 Serial Link using Wake-up function