Hi,
I'm having a problem getting the i2c SCL frequency as documented by the i2c user guide.
SYSCLK = 40.0 MHz, prescale divider IPSC = 3 -> module clk = 10.0 MHz
With IPSC = 3 -> d = 5, the SCL frequency should be: 10 MHz / (CCLL+5+CCLH+5)
ICCLL/H = 6, div = 22 -> SCLcalc = 454.5 kHz, SCLmeasured = 368.3 kHz
ICCLL/H = 8, div = 26 -> SCLcalc = 384 kHz, SCLmeasured = 323 kHz
ICCLL/H = 16, div = 42 -> SCLcalc = 238 kHz, SCLmeasured = 213 kHz
ICCLL/H = 20, div = 50 -> SCLcalc = 200 kHz, SCLmeasured = 182.1 kHz
Measured on logic channels on an agilent MSO.
It seems that the frequency formula is more like 10 MHz / (CCLL + CCLH + 3*5) ?
Anyone experienced similar differences ?
cheers