From 57108c2c7ee9d49da91e268983c9560467ce2880 Mon Sep 17 00:00:00 2001
From: Dreaded_X <tim.huizinga@gmail.com>
Date: Sun, 17 Jan 2021 16:10:47 +0100
Subject: [PATCH] Tried adjusting speed to be more accurate and added random
 device (does not exist im real hardware yet)

---
 Makefile     |  9 +++++----
 src/main.cpp | 34 ++++++++++++++++++++++++++++++----
 2 files changed, 35 insertions(+), 8 deletions(-)

diff --git a/Makefile b/Makefile
index aba1d9b..1307c82 100644
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,12 @@
-CXX = g++
+PREFIX=
+CXX = $(PREFIX)g++
 BUILD = .build
 TARGET = emulator
 OPT = g -g
 DEFINE = -DCPU_Z80_STATIC -DCPU_Z80_USE_LOCAL_HEADER
 
-CFLAGS = -Wall -Wextra -std=c++20 -O$(OPT) $(DEFINE) -flto -Iinclude `sdl2-config --cflags` -Ilibs/z80/API/emulation/CPU -Ilibs/z/API
-LDFLAGS = -Wall -Wextra -O$(OPT) -flto `sdl2-config --libs` -lSDL2_image
+CFLAGS = -Wall -Wextra -std=c++20 -flto -O$(OPT) $(DEFINE) -Iinclude `$(PREFIX)pkg-config --cflags sdl2` -Ilibs/z80/API/emulation/CPU -Ilibs/z/API
+LDFLAGS = -Wall -Wextra -flto -O$(OPT) `$(PREFIX)pkg-config --libs sdl2` `$(PREFIX)pkg-config --libs SDL2_image` -mconsole
 
 SRC = \
 src/main.cpp \
@@ -30,7 +31,7 @@ $(BUILD)/%.o: %.c Makefile | $(BUILD)
 	$(CXX) -c $(CFLAGS) $< -o $@
 
 $(BUILD)/$(TARGET): $(OBJ) Makefile
-	$(CXX) $(LDFLAGS) $(OBJ) -o $@
+	$(CXX) $(OBJ) -o $@ $(LDFLAGS)
 
 $(BUILD):
 	mkdir $@
diff --git a/src/main.cpp b/src/main.cpp
index 3e78b74..78be83d 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,5 +1,5 @@
-#include <bits/stdint-uintn.h>
 #include <chrono>
+#include <cstdlib>
 #include <cstring>
 #include <fstream>
 #include <stdexcept>
@@ -8,6 +8,7 @@
 #include <functional>
 #include <string>
 #include <queue>
+#include <random>
 
 #include <SDL2/SDL.h>
 #include <SDL2/SDL_error.h>
@@ -22,6 +23,7 @@
 #include "SDL_keyboard.h"
 #include "SDL_keycode.h"
 #include "SDL_pixels.h"
+#include "SDL_scancode.h"
 #include "SDL_surface.h"
 #include "Z/types/base.h"
 #include "Z80.h"
@@ -31,6 +33,9 @@
 #define SD_PAGE_SIZE 512
 #define CPM_PAGES (SD_PAGE_SIZE/CPM_PAGE_SIZE*SD_PAGES)
 
+// @todo Make this commandline parameter
+#define CLOCK_SPEED 4000e4
+
 struct Glyph {
 	uint8_t c = 0x00;
 	int fg = 0b111;
@@ -388,7 +393,7 @@ class Disk {
 template <int W, int H>
 class Emulator {
 	public:
-		Emulator(std::filesystem::path rom_name, std::filesystem::path disk_name, std::string startup = "") : memory(rom_name), disk(disk_name) {
+		Emulator(std::filesystem::path rom_name, std::filesystem::path disk_name, std::string startup = "") : memory(rom_name), disk(disk_name), rd(), gen(rd()), dist(0x00, 0xFF), begin(std::chrono::steady_clock::now()), wait(0) {
 			// SDL
 			int render_flags = SDL_RENDERER_ACCELERATED;
 			int window_flags = 0;
@@ -477,6 +482,11 @@ class Emulator {
 				case 0x03:
 					return 0x01;
 
+				// @note This is not implemented in the hardware yet
+				case 0x09: {
+					return e->dist(e->gen);
+				}
+
 				// Input
 				case 0x1E: {
 					uint8_t c = e->input.front();
@@ -541,7 +551,12 @@ class Emulator {
 		}
 
 		void update() {
-			z80_run(&z, 1);
+			auto diff = std::chrono::steady_clock::now() - begin;
+			if (diff > wait) {
+				begin = std::chrono::steady_clock::now();
+				size_t cycles = z80_run(&z, 1);
+				wait = std::chrono::nanoseconds((long)std::floor(10e9 * cycles / CLOCK_SPEED)) - (diff - wait);
+			}
 		}
 
 		void draw_screen() {
@@ -605,6 +620,9 @@ class Emulator {
 						// @todo For some reason we cannot capture ctrl???
 						if (SDL_GetModState() & KMOD_ALT && c == 'c') {
 							input.push(0x03);
+						// @todo Even more strange behaviour in windows
+						} else if (SDL_GetModState() & KMOD_CTRL && c == ' ') {
+							input.push(0x03);
 						} else {
 							input.push(c);
 						}
@@ -640,8 +658,14 @@ class Emulator {
 		Memory memory;
 		Disk disk;
 
+		std::random_device rd;
+		std::mt19937 gen;
+		std::uniform_int_distribution<> dist;
+
 		std::queue<uint8_t> input;
-		bool ctrl = false;
+
+		std::chrono::steady_clock::time_point begin;
+		std::chrono::nanoseconds wait;
 };
 
 int main(int argc, char* argv[]) {
@@ -665,4 +689,6 @@ int main(int argc, char* argv[]) {
 			e.render();
 		}
 	}
+
+	return 0;
 }