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| -rw-r--r-- | README.md | 13 |
1 files changed, 9 insertions, 4 deletions
@@ -254,7 +254,7 @@ By simply looking at this you quickly know that: Even if the name turns out to not be too flashy, it's imperative when writing assembly code to be as clear as possible. -## UPPER_CASE for macros and aliases to memory-mapped I/O +## UPPER_CASE for macros and regular constants In a similar spirit as many code styles for C, use `UPPER_CASE` for macros, as that makes it more apparent what they are. @@ -269,13 +269,18 @@ that makes it more apparent what they are. .endmacro ``` -In a similar way, there are some assignments which are simply aliases to -memory-mapped I/O. These "variables" are to be defined also in upper case as -they are quite special. +In a similar way, there are assignments which are simply a way to name regular +numeric constants. This differs to how "variables" are assigned as they are not +memory addresses that the CPU can directly access. Hence, for constant numbers +or memory addresses which are not directly tied to the CPU (i.e. memory-mapped +I/O), use upper case in the same way you would in C. ``` assembly lda PPU::m_control ; bad! lda PPU::CONTROL ; good! + +bad_constant = 1 +GOOD_CONSTANT = 1 ``` # Calling conventions |