Adding new docs(markdown) for holding thoughts/ideas on design of i2c and multiple mcu support.

i2c_design.md

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+# I2C Design
+
+# API / Interface
+
+Ideally the interface should be as simple and portable as possible.
+
+We don't want the consummer/user of the interface to need to worry about all
+the details of implimentation.
+
+For instance the end-user should be able to in one line setup an I2C bus
+and on a second line to send or receive data.
+
+
+I have some functions that I think should ideally be "privite" in normal usage.
+But I need to still be able to access those functions or methods during the
+testing.
+
+
+## Error handling
+
+Errors need to be handled such that the end-user doesn't miss this information.
+
+## Timeouts
+
+Sometimes there is errors in hardware or bus/hardware failures. These need to
+be found quickly and handled.
+
+
+
+## Sharing
+
+The I2C bus needs to be shared sometimes. I need to figure out some ways to
+ensure safe sharing of the bus/resources.
+
+I think maybe the sharing should be implimented externally to the HAL.
+
+
+
+
+

mcu_support.md

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+# MCU Support
+
+One issue of note is the need to support multiple families and chipsets.
+
+For the moments I'm assumign I can use the defines from the CH32FUN project's
+headers to handle this issue.
+
+The other point of interest is that the linker file and toolchain file will
+need to be modified to conditionally select options.
+
+Maybe I need to create multiple linker files, I'm unsure.
+
+
+I also don't know if the newer MCUs in the CH32V00X series have alternate boot
+modes or what.
+
+
+