Does anyone know, whether the PCA could be driven by the SmaRTClock / 8 (I am using a C8051F920)? The datasheet is somehow ambigiuous : the option is mentioned in the text, but not shown at the PCA0MD register settings. On the other side, the configuration wizard gives an option to select the SmaRTClock as input to the PCA, but I have not been able to confirm this. Is there a known solution to achive this?

Thanks a lot!!

Does anyone know, whether the PCA could be driven by the SmaRTClock / 8 (im am using a C8051F300)?
Erm...Sorry, but I couldn't locate anything regarding a integrated SmaRTClock feature in the F300 datasheet...

Regards,

Sorry for the confusion, the question relates to the C8051F920 and NOT the C8051F300 (I have two projects running simultaneously ...). The statement can be found on page 300 of the Datasheet (Rev 1.1).

Regards pipistrellus

...the question relates to the C8051F920...
Ah, now it's getting better...

Your're right, I couldn't also locate anything regarding the PCA0MD settings for SmaRTClock/8 as clock source. Table 26.1 and SFR definition 26.2 both only show six sources.
Please report this to SiLabs (https://www.silabs.com/support/pages/contacttechnicalsupport.aspx).

The good news: You only have two possible settings left in PCA0MD to try it out

Regards,

Thanks for the confirmation. I tried both options, whereby the PCA is either not clocked or is clocked at a rather high rate (probably the system clock). So the question remaining is, whether there is another option to route the SmaRTClock to the PCA or not.

I tried both options, whereby the PCA is either not clocked or is clocked at a rather high rate (probably the system clock).
1) Which value for CPS2-0 flags? 110? According to the configuration wizard this would be the setting if SmaRTClock / 8 is choosen as clock input to PCA.
2) Are you sure that the PCA is then fed with a clock really higher than SmaRTClock / 8?
3) What is the clock source for SmaRTClock?

So the question remaining is, whether there is another option to route the SmaRTClock to the PCA or not.
Assuming that the chip die has errors and it's really not possible to feed PCA from SmaRTClock, the only other way I could imagine (and only maybe work) is as follows:
1) If no external crystal is used, configure for external crystal on XTAL3 and XTAL4 and short them together. Apply the appropriate crossbar settings. This step can be void if external crystal is already used.
2) Connect the output port pin of RTC crystal oscillator to the ECI input (enable it in crossbar) from the PCA. This will give PCA clock = SmaRTClock, but if it works it's better than no clock...

Regards,

Thanks for your assistance. Yes, I tried with CPS set to 110. The system clock runs at 2,5 MHz (internal oscillator) and the SmarRTClock on a 32,768 kHz crystal. So the difference should be obvious ...

Many thanks for your suggestion of a workaround. I will try it out early next week.