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Update some broken anchor links (#1444)

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Philipp Oppermann
2025-12-08 17:31:52 +01:00
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parent 86c36479cf
commit 211f460251
56 changed files with 387 additions and 387 deletions
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blog/content/edition-1/posts/04-printing-to-screen/index.md
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@@ -26,25 +26,25 @@ This post uses recent unstable features, so you need an up-to-date nighly compil
## The VGA Text Buffer
The text buffer starts at physical address `0xb8000` and contains the characters displayed on screen. It has 25 rows and 80 columns. Each screen character has the following format:
Bit(s) | Value
------ | ----------------
0-7 | ASCII code point
8-11 | Foreground color
12-14 | Background color
15 | Blink
| Bit(s) | Value |
| ------ | ---------------- |
| 0-7 | ASCII code point |
| 8-11 | Foreground color |
| 12-14 | Background color |
| 15 | Blink |
The following colors are available:
Number | Color | Number + Bright Bit | Bright Color
------ | ---------- | ------------------- | -------------
0x0 | Black | 0x8 | Dark Gray
0x1 | Blue | 0x9 | Light Blue
0x2 | Green | 0xa | Light Green
0x3 | Cyan | 0xb | Light Cyan
0x4 | Red | 0xc | Light Red
0x5 | Magenta | 0xd | Pink
0x6 | Brown | 0xe | Yellow
0x7 | Light Gray | 0xf | White
| Number | Color | Number + Bright Bit | Bright Color |
| ------ | ---------- | ------------------- | ------------ |
| 0x0 | Black | 0x8 | Dark Gray |
| 0x1 | Blue | 0x9 | Light Blue |
| 0x2 | Green | 0xa | Light Green |
| 0x3 | Cyan | 0xb | Light Cyan |
| 0x4 | Red | 0xc | Light Red |
| 0x5 | Magenta | 0xd | Pink |
| 0x6 | Brown | 0xe | Yellow |
| 0x7 | Light Gray | 0xf | White |
Bit 4 is the _bright bit_, which turns for example blue into light blue. It is unavailable in background color as the bit is used to control if the text should blink. If you want to use a light background color (e.g. white) you have to disable blinking through a [BIOS function][disable blinking].
@@ -441,7 +441,7 @@ But we can't use it to print anything! You can try it yourself in the `print_som
To resolve it, we could use a [mutable static]. But then every read and write to it would be unsafe since it could easily introduce data races and other bad things. Using `static mut` is highly discouraged, there are even proposals to [remove it][remove static mut].
[mutable static]: https://doc.rust-lang.org/1.30.0/book/second-edition/ch19-01-unsafe-rust.html#accessing-or-modifying-a-mutable-static-variable
[mutable static]: https://doc.rust-lang.org/book/ch20-01-unsafe-rust.html#accessing-or-modifying-a-mutable-static-variable
[remove static mut]: https://internals.rust-lang.org/t/pre-rfc-remove-static-mut/1437
But what are the alternatives? We could try to use a cell type like [RefCell] or even [UnsafeCell] to provide [interior mutability]. But these types aren't [Sync] \(with good reason), so we can't use them in statics.