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MSM66573 Family User's Manual
Chapter 12 Serial Port Functions
12
(3)
SIO1 receive control register (SR1CON)
Reset bit 0 (SR1MOD) to "0" to change the mode to UART mode. Specify the receive data
length with bit 1 (SR1LN). Specify with bit 2 (S1EXC) whether the baud rate clock is internal
(overflow output of timer 4) or external (RXC1). Specify whether there is parity with bit 4
(SR1PEN). If parity is selected, specify the parity bit logic with bit 5 (SR1ODD). With bit
6 (RC1IE), specify whether interrupt requests are enabled or disabled when a receive
complete signal occurs. If bit 7 (SR1REN) is set to "1", reception is enabled and the
reception operation is performed when data arrives.
12.5.3.2 Synchronous Mode Settings
Transmit settings
(1)
Port 8 mode register (P8IO)
If TXD1 (transmit data output) is to be used, set bit 1 (P8IO1) to "1" to configure that port
as an output. If the transmit clock is to be output externally (master mode), set bit 3 (P8IO3)
to "1" to configure that port as an output. If the baud rate clock is to be input externally (slave
mode), reset bit 3 (P8IO3) to "0" to configure that port as an input.
(2)
Port 8 secondary function control register (P8SF)
If TXD1 (transmit data output) is to be used, set bit 1 (P8SF1) to "1" to configure that port
as a secondary function output. If the transmit clock is to be output externally (master
mode), set bit 3 (P8SF3) to "1" to configure that port as a secondary function output. If the
baud rate clock is to be input externally (slave mode), specify with bit 3 (P8SF3) whether
the input will be pulled-up.
(3)
SIO1 transmit control register (ST1CON)
Set bit 0 (ST1MOD) to "1" to specify the mode to synchronous mode. Specify the transmit
data length with bit 1 (ST1LN). Specify master or slave mode transmission with bit 3
(ST1STB). With bit 6 (TR1MIE), specify whether interrupt requests are enabled or disabled
when a transmit buffer empty signal occurs. With bit 7 (TR1NIE), specify whether interrupt
requests are enabled or disabled when a transmit complete signal occurs.
(4)
SIO1 transmit-receive buffer register (S1BUF)
Transmission is started by writing the transmit data to S1BUF.