SN8P2714X_2715
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 51
V1.4
7.1.5 External RC Oscillator Frequency Measurement
There is one way to get the Fosc frequency of external RC oscillator by instruction cycle (Fcpu). We can get the Fosc
frequency of external RC from the Fcpu frequency. The sub-routine to get Fcpu frequency of external oscillator is as
the following.
Example: Fcpu instruction cycle of external oscillator
B0BSET
P2M.0
; Set P2.0 to be output mode for outputting Fcpu toggle
signal.
@@:
B0BSET
P2.0
; Output Fcpu toggle signal in low-speed clock mode.
B0BCLR
P2.0
; Measure the Fcpu frequency by oscilloscope.
JMP
@B