C165H Datasheet, PDF (426/499 Pages) Infineon Technologies AG – EMBEDDED C166 WITH USART IOM-2 AND HDLC SUPPORT

C165H
System Control Unit (CSCU)
Bit
Function
FOSS
Frequency Output Signal Select
0: Output of the toggle latch: DC=50%.
1: Output of the reload counter: DC depends on FORV.
FOEN
Frequency Output Enable
0: Frequency output generation stops when signal f_OUT is/gets low.
1: FOCNT is running, f_OUT is gated to pin. 1st reload after 0-1 transition.
Note: It is not recommended to write to any part of bitfield FOCNT, especially not while
the counter is running. Writing to FOCNT prior to starting the counter is obsolete
Y ^{because it will immediatley be reloaded from FORV. Writing to FOCNT during}
operation may produce uninteded counter values.
R _{Output Frequency Calculation}
The output frequency can be calculated as f_OUT = f_CPU / ( (FORV+1) * 2^(1-FOSS) ),
A _{so fOUTmin = fCPU / 128 (FORV = 3FH, FOSS = ’0’),}
and f_OUTmax = f_CPU / 1 (FORV = 00_H, FOSS = ’1’).
IN ^- _fCPU
IM ^{PT 1)}
f_OUT
(FORV=0)
L ^{R 2)}
E ^{E 1)}
f_OUT
R C (FORV=2)
2)
P ^{X 1)}
E ^fOUT
(FORV=5)
- ²⁾
FOEN-->’1’
1) FOSS=’1’, output of counter
2) FOSS=’0’, output of toggle latch
The counter starts here
FOEN-->’0’
The counter stops here
Figure 136 Signal Waveforms
Note: The output signal (for FOSS=’1’) is high for the duration of 1 f_CPU cycle for all reload
values FORV > 0. For FORV = 0 the output signal corresponds to f_CPU.
Data Sheet
426
2001-04-19