From 3be1ce457b59b0dce62753858d820126a36491f4 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Sun, 5 Jun 2016 14:05:31 -0400
Subject: [PATCH] Made some attempt at discerning fields.

---
 Components/6560/6560.cpp | 41 +++++++++++++++++++++++++++++++++++++---
 Components/6560/6560.hpp |  5 +++++
 2 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/Components/6560/6560.cpp b/Components/6560/6560.cpp
index f1fa17ce4..be4b4de5f 100644
--- a/Components/6560/6560.cpp
+++ b/Components/6560/6560.cpp
@@ -11,7 +11,7 @@
 using namespace MOS;
 
 MOS6560::MOS6560() :
-	_crt(new Outputs::CRT::CRT(65, 1, Outputs::CRT::DisplayType::NTSC60, 1))
+	_crt(new Outputs::CRT::CRT(65 * 4, 4, Outputs::CRT::DisplayType::NTSC60, 1))
 {
 	_crt->set_rgb_sampling_function(
 		"vec3 rgb_sample(usampler2D sampler, vec2 coordinate, vec2 icoordinate)"
@@ -22,12 +22,47 @@ MOS6560::MOS6560() :
 
 void MOS6560::set_register(int address, uint8_t value)
 {
-	printf("%02x -> %d\n", value, address);
+	switch(address)
+	{
+		case 0x0:
+			_interlaced = !!(value&0x80);
+			_first_column_location = value & 0x7f;
+		break;
+
+		case 0x1:
+			_first_row_location = value;
+		break;
+
+		case 0x2:
+			_number_of_columns = value & 0x7f;
+			_video_matrix_start_address = (uint16_t)((_video_matrix_start_address & 0x3c00) | ((value & 0x80) << 2));
+		break;
+
+		case 0x3:
+			_number_of_rows = (value >> 1)&0x3f;
+			_wide_characters = !!(value&0x01);
+		break;
+
+		case 0x5:
+			_character_cell_start_address = (uint16_t)((value & 0x0f) << 10);
+			_video_matrix_start_address = (uint16_t)((_video_matrix_start_address & 0x0400) | ((value & 0xf0) << 5));
+		break;
+
+		case 0xf:
+			// TODO: colours
+		break;
+
+		default:
+		break;
+	}
+
+	printf("%02x: %02x\n", address, value);
+	printf("%04x %04x [%d by %d from %d, %d]\n", _character_cell_start_address, _video_matrix_start_address, _number_of_columns, _number_of_rows, _first_column_location, _first_row_location);
 }
 
 uint16_t MOS6560::get_address()
 {
-	return 0;
+	return 0x1c;
 }
 
 void MOS6560::set_graphics_value(uint8_t value)
diff --git a/Components/6560/6560.hpp b/Components/6560/6560.hpp
index 027e69bfd..eedbf80f9 100644
--- a/Components/6560/6560.hpp
+++ b/Components/6560/6560.hpp
@@ -25,6 +25,11 @@ class MOS6560 {
 
 	private:
 		std::unique_ptr<Outputs::CRT::CRT> _crt;
+
+		bool _interlaced, _wide_characters;
+		uint8_t _first_column_location, _first_row_location;
+		uint8_t _number_of_columns, _number_of_rows;
+		uint16_t _character_cell_start_address, _video_matrix_start_address;
 };
 
 }