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HT80C51 User Manual
Peripheral Modules – Standard Serial Interface (SIO0)
Handshake Solutions
© Philips Electronics N.V. 2005
Page 41 of 132
In this mode none of the Timers are used and the clock comes from the serial clock input sio_clk_i.
SMOD = 1, Baud Rate = 1/32 of the frequency at sio_clk_i.
SMOD = 0, Baud Rate = 1/64 of the frequency at sio_clk_i.
To set the SMOD bit:
ORL
PCON,#80H. The address of PCON is 87H.
Serial Port in Mode 3:
The baud rate in mode 3 is variable and sets up exactly the same as in mode 1.