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Philips 89C51RX2 - UART baud rates

Clock frequency (in MHz):	(mhz)
Desired baud rate (in bps):	(bps)

Mode 0 and 2 uses fixed baud rates.
Bit SMOD1 in special function register PCON can be used to select different speeds.

In Mode 1 and 3 Timer 2 can be used as baud rate generator by setting bits TCLK and RCLK in special function register T2CON.

	6-clock mode	12-clock mode
Desired baud rate overflow rate (microseconds)	rate=mhz/(16bps)*	rate=mhz/(32bps)*
RCAP2X reload value for Timer 2	rel=65536-rate RCAP2H RCAP2L	rel=65536-rate RCAP2H RCAP2L
Real baud rate achieved with bau rate generator	bpsr=mhz/(16(65536-rel))*	bpsr=mhz/(32(65536-rel))*
Difference to the desired baud rate	var=(bpsr-bps)/bps	var=(bpsr-bps)/bps

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