Turns out that the PiHut has a tutorial webpage for just this problem! https://thepihut.com/blogs/raspberry-pi-tutorials/17209332-adding-a-real-time-clock-to-your-raspberry-pi
Thanks for all the help! Rick On Tue, Apr 18, 2023, at 11:06 PM, Rick Thomas wrote: > Thanks very much, Pabs! I will follow up on those links and hopefully > get a better understanding of what is going on and why. Perhaps the > next time someone has a question like mine, I'll be able to be as > helpful to them as the folks here have been to me! > > Rick > > On Tue, Apr 18, 2023, at 4:57 PM, Paul Wise wrote: >> On Mon, 2023-04-17 at 22:21 -0700, Rick Thomas wrote: >> >>> What would have been even greater is if the error messages include >>> references to some documentation that explained the problem and gave >>> some clues to the larger context in which the problem arose. >> >> The messages I sent that patch adding are for very simple issues; >> "/proc not mounted", "/sys not mounted" and "i2c-dev not loaded" and >> since they all have very simple solutions, I just added the commands >> to fix them instead of pointers to documentation about each error. >> >> Probably the i2c manual pages should get some links to the Linux kernel >> documentation and wiki for I2C. I'm unlikely to work on that though, >> hopefully someone else is willing to do that. >> >>> For example, I'd like to know why it chose bus3 rather than one of >>> the other busses (0,1,2,4)? >> >> I expect that depends on the bus driver code for your device, >> those do not seem to document their ordering though and it >> looks like your particular i2c bus driver has no documentation. >> >> https://www.kernel.org/doc/html/latest/i2c/busses/index.html >> >>> I'd also like to know what the various modules do and what kinds of >>> parameters there are to influence the detailed behavior? >> >> Looks like the devices are defined by DeviceTree, ACPI, board files, >> dynamically by drivers for other devices, hardware probing or sysfs: >> >> https://www.kernel.org/doc/html/latest/i2c/instantiating-devices.html >> >>> And where is the documentation for the magic writing into /sys ? >> >> Seems to be here: >> >> https://www.kernel.org/doc/html/latest/i2c/instantiating-devices.html#method-4-instantiate-from-user-space >> https://www.kernel.org/doc/html/latest/i2c/i2c-sysfs.html >> >> These may also be useful: >> >> https://www.kernel.org/doc/html/latest/i2c/ >> https://archive.kernel.org/oldwiki/i2c.wiki.kernel.org/ >> >> PS: I am subscribed, no need to CC me, please respect Reply-To. >> >> -- >> bye, >> pabs >> >> https://wiki.debian.org/PaulWise >> >> Attachments: >> * signature.asc