Contributing
This chapter concerns the writers of this tutorial. When writing, there are a few standards to follow in order to maximize consistency throughout the tutorial.
This section concerns the way addresses are written, as to avoid confusion.
- For the sake of simplicity and explanation, all direct page addresses ("
$xx") shall use address$7E0000as its base. This shall be emphasized in code block comments, as well as explanations.
Example:
LDA #$42
STA $08 ; Store the value $42 into address $7E0008
- All absolute addresses ("$xxxx") use address
$7E0000as its base, if the address is between $0000-$7FFF inclusive. For addresses between $8000-$FFFF, address$000000shall be used as its base instead. This shall be emphasized in code block comments, as well as explanations.
Example:
LDA $8002 ; Load the value at address $008002 into A
STA $1008 ; Store that value into address $7E1008
This section concern the styling of the document.
- All opcodes and instructions shall be surrounded by the markdown backtick (`), regardless of the context.
Example: The opcode
LDA is used to load values into the A register. Thus, LDA #$49 loads the value $49 into A. This then can be increased to the value $4A by using INC A.- Sentences and phrases within table cells generally shouldn't end with a period.
- Tables introducing opcodes should have the opcodes in bold and have at least the three columns in below example:
Opcode | Full name | Explanation |
LDA | Load into accumulator | Load a value into A |
This section concerns the usage of certain words in certain context.
Rule | Example |
When referring to the Ricoh 5A22 processor, use the SNES instead | The SNES is capable of entering 8-bit or 16-bit mode |
When referring to a specific area in the SNES memory, always prepend address to it, preferably with the memory area (i.e. RAM) | (The) RAM address $7E0000 contains [...] |
When referring to the accumulator (A) or the index registers (X and Y), just use A, X or Y | A is now in 8-bit mode. X is used to index addresses |
When referring to values, always prepend value to it | A contains the value $00 |
- Code shall use indentation when there are labels, sublabels or plus/minus labels on the same line as an instruction. The amount of indentation equals the length of the longest aforementioned type of label in the code block, including colon ("
:"), plus two additional spaces.- Code shall use whitespace for indentation, not tabs.
- Opcodes are written entirely in uppercase (e.g.:
LDA). - Labels are written in PascalCase (e.g.:
Label1:). - Sublabels are written entirely in lower, underscore-case and the name should semantically suit the parent label, without redundancy (e.g.:
.return). - Defines are written in PascalCase (e.g.:
!SomeDefine). - Direct data (
db,dw,dl,dd), indexers (,x,,y,,s) and opcode length specifiers (.b,.w,.l) are written entirely in lowercase. - Comment indicators (i.e.
;) shall start on column 20, and left-padded by whitespace, not tabs.- If there's no space for a comment on column 20, it should start on the same line anyway.
- In fact, never use tabs.
- Comment indicators shall be followed by a whitespace, before the comment itself.
- There will be an extra new line after the opcodes
RTS,RTL,RTI,JMP,JML,BRA,BRL. - These are guidelines which are to be followed as strictly as possible, but there may be exceptional cases. Use your best judgment.
Examples:
SomeLabel: ; This label is on its own line
LDA.b #$42
STA $00 ; This is a comment
RTS
.table:
db $01,$02,$03,$04 ; Another comment
.second_table:
db $01,$02,$03,$04,$01,$02,$03,$04 ; An exceptional comment
TestLabel: LDA #$02 ; This label is on the same line as an instruction
STA $01
BNE +
NOP
+ RTS ; The code is indented according to "TestLabel", not "+"
Last modified 1yr ago