SM39A16M1
8-Bit Micro-controller
16KB with ISP Flash
& 1K+256B RAM embedded
the function it performs such as parity check, multiprocessor communication etc.
RB8: In modes 2 and 3, it is the 9th data bit received. In mode 1, if SM2 is 0, RB8 is the stop
bit. In mode 0, this bit is not used. Must be cleared by software.
TI: Transmit interrupt flag, set by hardware after completion of a serial transfer. Must be
cleared by software.
Receive interrupt flag, set by hardware after completion of a serial reception. Must be
cleared by software.
RI:
9.1 Serial interface
The Serial Interface can operate in the following 4 modes:
SM0
SM1
Mode
Description
Shift register
8-bit UART
9-bit UART
9-bit UART
Board Rate
0
0
1
1
0
1
0
1
0
1
2
3
Fosc/12
Variable
Fosc/32 or Fosc/64
Variable
Here Fosc is the crystal or oscillator frequency.
9.1.1 Mode 0
Pin RXD serves as input and output. TXD outputs the shift clock. 8 bits are transmitted with LSB first. The baud rate is
fixed at 1/12 of the crystal frequency. Reception is initialized in Mode 0 by setting the flags in SCON as follows: RI = 0
and REN = 1. In other modes, a start bit when REN = 1 starts receiving serial data. As shown in Fig. 9-1 and Fig. 9-2
Fig. 9-1: Transmit mode 0
Fig. 9-2: Receive mode 0
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M069
Ver C SM39A16M1 7/31/2013
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SYNCMOS [ SYNCMOS TECHNOLOGIES,INC ]
