Editing Spec.isa (section)

== Settings ==
The <code>[settings]</code> section defines several configuration properties for your ISA:

=== name ===
<pre>
name = "Architecture name"
name = architecture_name
</pre>
Names the architecture this ISA specifies.  It can be either a string or an identifier.

=== variant ===
<pre>
variant = "Architecture variant"
</pre>
Additional text that can be used to describe the ISA.

=== endianness ===
Defines the byte order of the instructions.
<pre>
endianness = big
endianness = little
</pre>
The default is big endian.

For example, if we have an instruction defined as <code>11110000 00001111</code> then:
* <code>big</code> endian will encode the instruction as <code>240 15</code>.
* <code>little</code> endian will encode the same instruction as <code>15 240</code>.
(as shown in, for example, the {{Component|ROM||alpha}} component)

{{note|type=info|The ROM component has it's own endianness flag, which can reverse the byte order again.  This is straightforward if your instruction width happens to match the ROM's bit width, but can be confusing if the widths differ.}}

=== line_comments ===
Specifies the tokens used to mark the start of a single-line comment.  Single-line comments start at the given token and consume the remainder of the line.
<pre>
line_comments = "#"
line_comments = [";", "//"]
</pre>
The default line_comments value is <code>[";", "//"]</code>.
{{note|type=info|Any parenthesis style cam be used for the list syntax: <code>[]</code>, <code>()</code> or <code>{}</code>.}}
{{note|type=warn|While the compiler respects the <code>line_comments</code> setting, the syntax highlighter in the assembler window currently only recognizes the default tokens.}}

=== block_comments ===
Specifies the tokens used to mark the start and end of a block comment.  Block comments start at the first token and consume everything up to the final token.  This includes line breaks as well as additional block comment start tokens (preventing block comments from being nested).
<pre>
block_comments = {"/*":"*/"}
</pre>
The default block_comments value is <code>{"/*":"*/}</code>.
{{note|type=info|Any parenthesis style cam be used for the list syntax: <code>[]</code>, <code>()</code> or <code>{}</code>.}}
{{note|type=warn|While the compiler respects the <code>line_comments</code> setting, the syntax highlighter in the assembler window currently does not - not even the default tokens.}}