Naming

General

• CamelCase is used to indicate different parts of a name.
• Underscores are used for the MCU’s register addresses, bits, and values.¹
• Modules begin uppercase.
• All exported items begin uppercase (but see RECORD fields).
• CONSTs begin uppercase.
• TYPEs begin uppercase.
• RECORD fields begin lowercase, even if exported.
• VARs begin lowercase (unless exported).
• Exported PROCEDUREs begin uppercase, local (non-exported) ones lowercase.
• PROCEDURE parameters begin lowercase.
• If a part of the CamelCase-ed name is an all-caps acronym, then the next part begins lowercase, such as SPIdev, to preserve the acronym.

Remarks

• I prefer local procedures to start lowercase, since this way I know when reading code if a procedure is part of the module API.
• Naming exported items should take into account that they will always be referred to qualified by their module name. For example, UARTdev.Device, not UARTdev.UARTdevice.
• Some exceptions due to the Oberon tradition: writer and reader variables are usually W and R, respectively.