C517A Datasheet, PDF (40/72 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

C517A
Serial Interfaces 0 and 1
The C517A has two serial interfaces which are functionally nearly identical concerning the
asynchronous modes of operation. The two channels are full-duplex, meaning they can transmit
and receive simultaneously. The serial channel 0 is completely compatible with the serial channel
of the C501 (one synchronous mode, three asynchronous modes). Serial channel 1 has the same
functionality in its asynchronous modes, but the synchronous mode and the fixed baud rate UART
mode is missing.
The operating modes of the serial interfaces is illustrated in table 9. The possible baudrates can be
calculated using the formulas given in table 10.
Table 9
Operating Modes of Serial Interface 0 and 1
Serial ^Mode
Interface
0
0
1
2
3
1
A
B
S0CON
SM0 SM1
0
0
0
1
1
0
1
1
–
–
–
–
S1CON Description
SM
– Shift register mode
Serial data enters and exits through R×D0;
T×D0 outputs the shift clock; 8-bit are
transmitted/received (LSB first); fixed baud rate
– 8-bit UART, variable baud rate
10 bits are transmitted (through T×D0) or
received (at R×D0)
– 9-bit UART, fixed baud rate
11 bits are transmitted (through T×D0) or
received (at R×D0)
– 9-bit UART, variable baud rate
Like mode 2
0 9-bit UART; variable baud rate
11 bits are transmitted (through T×D1) or
received (at R×D1)
1 8-bit UART; variable baud rate
10 bits are transmitted (through T×D1) or
received (at R×D1)
Semiconductor Group
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