Posted on August 07, 2013 at 11:41I'm using the BEEP function of my STM8S105, but it doesn't work as expectet.
It's not that I need the exact frequency, but I want to know, why it
differs from the correct vallue, when chosing HSE as timebase.
Basic settings:
- external quartz crystal 16MHz
- MCU options:
EXTCLK: External Oscillator (OPT4 EXTCLK = 0)
PRSC: 16MHz to 128kHz (OPT4 PRSC[1:0] = 00)
- BEEP_CSR = 0xCE
1st test:
option CKAWUSEL:
High Speed External
(OPT4 CKAWUSEL = 0)
-> expected fBEEP: 4kHz; real result: 2.69kHz
:
o
(
????
2nd test:
- option CKAWUSEL:
Low Speed Internal
(OPT4 CKAWUSEL = 1)
-> expected fBEEP: 4kHz; real result: 4.09kHz
:
o
)
Any clue???
TIA,
WoRo
#beep #ckawusel #lsi
