n-channel

commit aac558f8a7a7670e1965637a5f8a64b011039259
parent 3c1904252a6c0afedb50ce154067f734b0087867
Author: Samdal <samdal@protonmail.com>
Date:   Thu, 20 Feb 2025 19:25:26 +0100

add terminal seksjon i vga kontroller

Diffstat:
M
_posts/2024-05-08-VGA-Kontroller.md
 | 
128
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A
assets/images/VGA/VGA_fig19.jpeg
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0

2 files changed, 128 insertions(+), 0 deletions(-)
diff --git a/_posts/2024-05-08-VGA-Kontroller.md b/_posts/2024-05-08-VGA-Kontroller.md
@@ -688,3 +688,131 @@ void vga_text_mode_set_xy(int base_address, unsigned char x, unsigned char y, vg
   IOWR_32DIRECT(base_address, (y*80+x)*4, c.raw_word);
 }
 ```
+
+## C eksempel [Terminal]
+
+![Figur 19](/assets/images/VGA/VGA_fig19.jpeg)
+{: style="text-align: center; margin-bottom: 0px; padding-bottom: 0px"}
+Figur 19. Bilde av terminalen
+{: style="color:gray; font-size: 80%; text-align: center;"}
+```
+void random_tm(const char* cb)
+{
+  vga_set_mode(VGA_CONTROLLER_0_BASE, VGA_MODE_TEXT_MODE);
+  for (uint32_t i = 0; i < 80*30; i++) {
+    vga_text_mode_t c = {
+      .raw_word = rand() % 0xffff,
+    };
+    vga_text_mode_set(VGA_CONTROLLER_0_BASE, i, c);
+  }
+}
+
+struct commands {
+  void(*func)(const char* cb);
+  const char* name;
+  const char* desc;
+  int quit_immidiately;
+} commands[] = {
+  {cat,            "cat",                    "shows a picture of a cat"},
+  {gradient,       "gradient",               "RGB gradient"},
+  {cycle_rgb_slow, "cycle",                  "slowly cycle rgb", 1},
+  {0,              "clear",                  "clears screen", 1},
+  {display_char,   "char",                   "displays all combinations of arg1 (1 character)"},
+  {random,         "rand",                   "random colors"},
+  {random_tm,      "tmrand",                 "random colors text mode"},
+
+};
+
+#define vga_printstr(_base, _x, _y, _str) do {        \
+    for (uint32_t _i = 0; _i < strlen(_str); _i++) {  \
+      c.codepoint = (_str)[_i];                       \
+      vga_text_mode_set_xy(_base, _x, _y, c);         \
+      (_x)++;                                         \
+    }                                                 \
+  } while (0)
+
+#define vga_printstr_ln(_base, _x, _y, _str) do { \
+    vga_printstr(_base, _x, _y, _str);            \
+    (_y) += 1;                                    \
+    (_y) += (_x) / 80;                            \
+    (_x) = 0;                                     \
+  } while (0)
+
+int main() {
+clear_screen:
+  vga_clear_screen(VGA_CONTROLLER_0_BASE);
+  vga_set_mode(VGA_CONTROLLER_0_BASE, VGA_MODE_TEXT_MODE);
+  char command_buffer[128] = {0};
+  uint32_t x = 0;
+  uint32_t y = 0;
+  vga_text_mode_t c = {
+    .bg = 0,
+    .fg = 15,
+  };
+line_begin:
+  vga_printstr(VGA_CONTROLLER_0_BASE, x, y, "$> ");
+  for (;;) {
+    c.codepoint = 221;
+    c.blink = 1;
+    vga_text_mode_set_xy(VGA_CONTROLLER_0_BASE, x, y, c);
+    c.blink = 0;
+
+    unsigned char codepoint = getchar();
+
+    c.codepoint = 0;
+    vga_text_mode_set_xy(VGA_CONTROLLER_0_BASE, x, y, c);
+    if (codepoint == '\n' || codepoint == '\r') {
+      vga_printstr_ln(VGA_CONTROLLER_0_BASE, x, y, "");
+
+      for (uint32_t i = 0; i < sizeof(commands) / sizeof(*commands); i++) {
+          if (memcmp(commands[i].name, command_buffer, strlen(commands[i].name)) == 0) {
+            if (commands[i].func)
+              commands[i].func(command_buffer);
+            command_buffer[0] = 0;
+            if (!commands[i].quit_immidiately)
+              getchar();
+            goto clear_screen;
+          }
+      }
+      if (memcmp("help", command_buffer, strlen("help")) == 0) {
+        for (uint32_t i = 0; i < sizeof(commands) / sizeof(*commands); i++) {
+          vga_printstr(VGA_CONTROLLER_0_BASE, x, y, "> ");
+          vga_printstr(VGA_CONTROLLER_0_BASE, x, y, commands[i].name);
+          vga_printstr(VGA_CONTROLLER_0_BASE, x, y, " | ");
+          vga_printstr_ln(VGA_CONTROLLER_0_BASE, x, y, commands[i].desc);
+        }
+      } else if (*command_buffer != 0) {
+        if (strchr(command_buffer, ' ')) *strchr(command_buffer, ' ') = 0;
+        vga_printstr(VGA_CONTROLLER_0_BASE, x, y, "[term: error]: command '");
+        vga_printstr(VGA_CONTROLLER_0_BASE, x, y, command_buffer);
+        vga_printstr_ln(VGA_CONTROLLER_0_BASE, x, y, "' not found");
+      }
+      command_buffer[0] = 0;
+      goto line_begin;
+      continue;
+    }
+    if (codepoint == 127) {
+      if (x > 3) x--;
+      c.codepoint = 0;
+      vga_text_mode_set_xy(VGA_CONTROLLER_0_BASE, x, y, c);
+      command_buffer[x-3] = codepoint;
+      command_buffer[x-3+1] = 0;
+      continue;
+    }
+    c.codepoint = codepoint;
+    vga_text_mode_set_xy(VGA_CONTROLLER_0_BASE, x, y, c);
+    if (x-3 < sizeof(command_buffer)) {
+      command_buffer[x-3] = codepoint;
+      command_buffer[x-3+1] = 0;
+    }
+    x++;
+  }
+}
+```
+
+
+
+
+
+
+
diff --git a/assets/images/VGA/VGA_fig19.jpeg b/assets/images/VGA/VGA_fig19.jpeg
Binary files differ.