1 files changed, 69 insertions, 0 deletions
diff --git a/drivers/cga.h b/drivers/cga.h
new file mode 100644
index 0000000..f0ca412
--- /dev/null
+++ b/drivers/cga.h
@@ -0,0 +1,69 @@
+#pragma once
+#include <stdlib.h>
+#include "ports.h"
+
+/*
+ * CGA (Colour Graphics Adapter)
+ *
+ * useful links:
+ * https://www.seasip.info/VintagePC/cga.html
+ * https://www.lowlevel.eu/wiki/Color_Graphics_Adapter
+ *
+ * TODO: switching between modes
+ * TODO: cursor styling
+ */
+
+class CGA : public Console {
+public:
+  /* Hardware text mode colour constants. */
+  enum Colour : uint8_t {
+    CGA_COLOR_BLACK = 0,
+    CGA_COLOR_BLUE = 1,
+    CGA_COLOR_GREEN = 2,
+    CGA_COLOR_CYAN = 3,
+    CGA_COLOR_RED = 4,
+    CGA_COLOR_MAGENTA = 5,
+    CGA_COLOR_BROWN = 6,
+    CGA_COLOR_LIGHT_GREY = 7,
+    CGA_COLOR_DARK_GREY = 8,
+    CGA_COLOR_LIGHT_BLUE = 9,
+    CGA_COLOR_LIGHT_GREEN = 10,
+    CGA_COLOR_LIGHT_CYAN = 11,
+    CGA_COLOR_LIGHT_RED = 12,
+    CGA_COLOR_LIGHT_MAGENTA = 13,
+    CGA_COLOR_LIGHT_BROWN = 14,
+    CGA_COLOR_WHITE = 15,
+  };
+
+  CGA(Colour fg = CGA_COLOR_BLACK, Colour bg = CGA_COLOR_LIGHT_GREY, uint32_t address = 0xB8000);
+  ~CGA() = default;
+
+  void set_colour(Colour fg, Colour bg);
+
+  void enable_cursor(uint8_t start, uint8_t end);
+  void disable_cursor();
+  void update_cursor() override;
+
+  void write(char c) override;
+  void write(ViewIterator& iter) override;
+
+
+  struct Entry {
+    char c;
+    Colour fg : 4;
+    Colour bg : 4;
+  } __attribute((packed));
+
+private:
+  const size_t max_columns = 80, max_rows = 25;
+  size_t column = 0, row = 0;
+
+  Colour colour_fg;
+  Colour colour_bg;
+
+  Entry* buffer;
+
+  // ports
+  cga_idx_port p_idx;
+  cga_dat_port p_dat;
+};