I'm also sorry if this was not posted in the right section of the forum. It it's the case, please kindly indicate and I'll move it to the appropriate section.
Welcome in the forum!
In deep sleep the ILO frequency will be up to 60% off without a clock crystal. Not quite usable for an RTC.
Hi Bob, thanks for taking the time to answer me.
With this project, the goal is to switch to WCO instead of ILO except if there's something I didn't quite understand correctly.
As of my readings on documention for PSoC 4200M family, the WCO is supposed to be included
The PSoC 4200-M clock system is responsible for providing clocks to all subsystems that require clocks and for switching between different clock sources without glitching. In addition, the clock system ensures that no meta-stable conditions occur. The clock system for the PSoC 4200-M consists of a Watch Crystal Oscillator (WCO) running at 32 kHz, the IMO (3 to 48 MHz) and the ILO (32-kHz nominal) internal oscillators, and provision for an external clock."
On the same page, we can read the following:
The PSoC 4200M clock subsystem also includes a low-frequency crystal oscillator (32-kHz WCO) that is available during the Deep Sleep mode and can be used for Real-Time Clock (RTC) and Watchdog Timer applications."
Which seems to point that there should be all required parts included in the SoC no?
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You refer to the description of the PSoC4 M chip which provides all the needed connections (pins) for a WCO. The letter "C" stands for "Crystal" which is never integrated into a chip but is an external component.
Talking about the prototype board you bought, there is a lot of documentation including a schematic. Look at "Program Files (x86)\Cypress\ Here you find entries for all your installed kits. In the schematic .pdf file I couldn't find any crystal, so you would have to connect a watch crystal (with some caps) externally. See excerpt from schematic, you just have to connect the xtal between P0_5 and P0_5.
Ok thanks for clarifying the documentation. It's the "The PSoC 4200M clock subsystem also includes a low-frequency crystal oscillator (32-kHz WCO) " that got me confused but effectively I thought that I would need an external crystal and you just confirmed it.
Thank you again for the answers you provided.
You are always welcome!