SAB80C517-M16 SIEMENS [Siemens Semiconductor Group], SAB80C517-M16 Datasheet - Page 61

• Manufacturer Part Number: SAB80C517-M16
• Description: 8-Bit CMOS Single-Chip Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Figure 7-12
Special Function Register S1CON (Address 9B H )
Bit
SM
SM21
REN1
TB81
RB81
TI1
RI1
Figure 7-13
Special Function Register S1BUF (Address 9C H )
Receive and transmit buffer of serial interface 1. Writing to S1BUF loads the transmit register and
initiates transmission. Reading out S1BUF accesses a physically separate receive register.
Semiconductor Group
9C H
9B
H
SM
Function
SM = 0: serial mode A; 9-bit UART
SM = 1: serial mode B; 8-bit UART
Enables the multiprocessor communication feature in mode A. If SM21
is set to 1, RI1 will not be activated if the received 9th data bit (RB81) is
0. In mode B, if SM21 = 1, RI1 will not be activated if a valid stop bit was
not received.
Receiver enable of interface 1. Enables serial reception.
Set by software to enable reception. Cleared by software to disable
reception.
Transmitter bit 8 of interface 1. Is the 9th data bit that will be transmitted
in mode A. Set or cleared by software as desired.
Receiver bit 8 of interface 1. Is the 9th data bit that was received in
mode A. In mode B, if SM21 = 0, RB81 is the stop bit that was received.
Transmitter interrupt of interface 1. Is the transmit interrupt flag. Set by
hardware at the beginning of the stop bit in any serial transmission. Must
be cleared by software.
Receiver interrupt of interface 1. Is the receive interrupt flag.
Set by hardware at the halfway through the stop bit time in any serial
reception. Must be cleared by software.
š–
Serial interface 1 buffer register
SM21
REN1
62
TB81
On-Chip Peripheral Components
RB81
TI1
RI1
S1BUF
S1CON