Microcontroller
Peripheral Timing
Calculator

Philips 8xC591 - 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 the internal baud rate generator is used.
Bit SMOD1 in Special Function Register PCON can be used to select different speeds.

	SMOD1 = 1	SMOD1 = 0
Desired baud rate overflow rate (microseconds)	rate=mhz/(16bps)*	rate=mhz/(32bps)*
S0PS reload value for the 12-bit timer	rel=4096-rate	rel=4096-rate
Real baud rate achieved with bau rate generator	bpsr=mhz/(16(4096-rel))*	bpsr=mhz/(32(4096-rel))*
Difference to the desired baud rate	var=(bpsr-bps)/bps	var=(bpsr-bps)/bps

Upcoming Classes

All materials
provided 'as is'
see Disclaimer