commit 19c923ce69878795c42357d30351f45550a211ba
Author: chris <cwer542@gmail.com>
Date:   Mon Sep 22 01:57:51 2025 +0200

    init

diff --git a/.clang-format b/.clang-format
new file mode 100644
index 0000000..247acf1
--- /dev/null
+++ b/.clang-format
@@ -0,0 +1,3 @@
+# clang format config
+BasedOnStyle: Google
+IndentWidth: 4
diff --git a/.clang-tidy b/.clang-tidy
new file mode 100644
index 0000000..293d63b
--- /dev/null
+++ b/.clang-tidy
@@ -0,0 +1,4 @@
+# clang tidy config
+Checks: 'clang-diagnostic-*,clang-analyzer-*,bugprone-*'
+WarningsAsErrors: 'true'
+HeaderFilterRegex: 'include/\*\.h'
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..b881cb0
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+# git ignores
+*~
+build
+.vscode/c_cpp_properties.json
+.vscode/settings.json
diff --git a/.vscode/launch.json b/.vscode/launch.json
new file mode 100644
index 0000000..695296e
--- /dev/null
+++ b/.vscode/launch.json
@@ -0,0 +1,25 @@
+{
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "vice",
+            "request": "launch",
+            "name": "Launch Vice",
+            "preLaunchTask": "${defaultBuildTask}"
+        },
+        {
+            "type": "vice",
+            "request": "attach",
+            "name": "Attach Vice",
+            "hostname": "localhost",
+            "port": 6502,
+            "preLaunchTask": "${defaultBuildTask}"
+        },
+        {
+            "type": "6502",
+            "request": "launch",
+            "name": "Launch 6502",
+            "preLaunchTask": "${defaultBuildTask}"
+        }
+    ]
+}
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
new file mode 100644
index 0000000..cc11806
--- /dev/null
+++ b/.vscode/tasks.json
@@ -0,0 +1,13 @@
+{
+    "tasks": [
+        {
+            "type": "vs64",
+            "action": "build",
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            },
+            "label": "build project"
+        }
+    ]
+}
diff --git a/disk/userport_tester.d64 b/disk/userport_tester.d64
new file mode 100644
index 0000000..5192eec
Binary files /dev/null and b/disk/userport_tester.d64 differ
diff --git a/nano/sketch_sep20a/sketch_sep20a.ino b/nano/sketch_sep20a/sketch_sep20a.ino
new file mode 100644
index 0000000..5317eb2
--- /dev/null
+++ b/nano/sketch_sep20a/sketch_sep20a.ino
@@ -0,0 +1,153 @@
+#define DP_0 2
+#define DP_1 3
+#define DP_2 4
+#define DP_3 5
+#define AR 6
+#define CR 7
+
+#define STANDBY 0
+#define READ 1
+#define WRITE 2
+
+
+char count = 0;
+char delayAmount = 100;
+char textToSent[]  = "Hallo vom Arduino Nano!";
+
+char mode;
+
+char getScreenCode(char c) {
+  if (c >= 32 && c <= 63) {
+    return c;
+  } else if (c == 64) {
+    return 0;
+  } else if (c >= 65 && c <= 90) {
+    return c;
+  } else if (c == 91 || c == 93) {
+    return c - 64;
+  } else if (c == 95) {
+    return 111;
+  } else if (c >= 97 && c <= 122) {
+    return c - 96;
+  } else if (c == 124) {
+    return 93;
+  } else {
+    return 63;
+  }
+}
+
+void initMode(char mode) {
+
+  switch (mode) {
+    case WRITE:
+      pinMode(DP_0, OUTPUT);
+      pinMode(DP_1, OUTPUT);
+      pinMode(DP_2, OUTPUT);
+      pinMode(DP_3, OUTPUT);
+      break;
+    case STANDBY:
+    default:
+      pinMode(DP_0, INPUT);
+      pinMode(DP_1, INPUT);
+      pinMode(DP_2, INPUT);
+      pinMode(DP_3, INPUT);
+  }
+
+  pinMode(AR, OUTPUT);
+  pinMode(CR, INPUT);
+
+  digitalWrite(DP_0, LOW);
+  digitalWrite(DP_1, LOW);
+  digitalWrite(DP_2, LOW);
+  digitalWrite(DP_3, LOW);
+  digitalWrite(AR, LOW);
+  digitalWrite(CR, LOW);
+
+}
+
+void setup() {
+  delay(2000);
+  mode = STANDBY;
+  initMode(mode);
+
+  Serial.begin(9600);
+  
+}
+
+void send4Bit(char c) {
+
+  for (char i = 3; i >= 0; i--) {
+    char d = c >> i & 1;
+    Serial.print(d, DEC);
+  }
+
+  for (char i = 0; i < 4; i++) {
+    char d = c >> i & 1;
+    digitalWrite(i+2, d);
+  }
+  Serial.print(" ");
+  digitalWrite(AR, HIGH);
+
+  while (digitalRead(CR) == LOW) {}
+
+  while (digitalRead(CR) == HIGH) {}
+  digitalWrite(AR, LOW);
+
+  //delay(500);
+}
+
+void sendByte(char a, char byte) {
+  char upper = byte >> 4;
+  char lower = byte & 0b00001111;
+
+
+  Serial.print(a);
+  Serial.print(" ");
+  Serial.print(a, DEC);
+  Serial.print(" ");
+  Serial.print(byte, DEC);
+  Serial.print(" ");
+  send4Bit(upper);
+  send4Bit(lower);
+}
+
+void startWrite() {
+  Serial.print("start\n");
+  mode = WRITE;
+  initMode(mode);
+  digitalWrite(AR, LOW);
+
+  int i = 0;
+  char c, sc;
+  do {
+    c = textToSent[i];
+    sc = getScreenCode(c);
+    i++;
+    sendByte(c, sc);
+    //Serial.print(c, DEC);
+  } while (c != 0);
+
+  Serial.print("\n");
+
+  for (char i = 2; i < 8; i++) {
+    digitalWrite(i, LOW);
+  }
+
+  mode = STANDBY;
+}
+
+void loop() {
+
+  if (mode == WRITE) {
+
+  } else if (mode == READ) {
+    
+  } else {
+    startWrite();    
+  }
+
+  Serial.print("\nAAAAAAAA\n");
+
+  delay(20000);
+
+}
diff --git a/project-config.json b/project-config.json
new file mode 100644
index 0000000..e1b3c3c
--- /dev/null
+++ b/project-config.json
@@ -0,0 +1,15 @@
+{
+    "name": "c64_c_userport",
+    "description": "Project c64_c_userport",
+    "toolkit": "cc65",
+    "sources": [
+        "src/main.c",
+        "src/menu/menu.c",
+        "src/input.c"
+    ],
+    "build": "debug",
+    "definitions": [],
+    "includes": [],
+    "args": [],
+    "compiler": ""
+}
diff --git a/src/input.c b/src/input.c
new file mode 100644
index 0000000..af688e1
--- /dev/null
+++ b/src/input.c
@@ -0,0 +1,52 @@
+#include "input.h"
+
+unsigned short* PEVIOUS_KEY_MATRIX_CODE_PTR = (unsigned short*)0x00C5;
+unsigned short* CURRENT_KEY_MATRIX_CODE_PTR = (unsigned short*)0x00CB;
+unsigned char C_64_KEYBOARD_MATRIX[8][8] = {
+    {20 /*DEL*/, 13 /*RETURN*/, 29 /*CURSOR RIGHT*/, 136 /*F7*/, 133 /*F1*/, 134 /*F3*/, 135 /*F5*/, 145 /*CURSOR UP*/},
+    {'3' , 'w' , 'a', '4', 'z', 's', 'e', 255 /*LEFT SHIFT*/},
+    {'5' , 'r' , 'd', '6', 'c', 'f', 't', 'x'},
+    {'7' , 'y' , 'g', '8', 'b', 'h', 'u', 'v'},
+    {'9' , 'i' , 'j', '0', 'm', 'k', 'o', 'n'},
+    {'+' , 'p' , 'l', '-', '.', ':', '@', ','},
+    {92 /*₤*/ , '*' , ';', 147 /*CLR*/, 255 /*RIGHT SHIFT*/, '=', 94 /*↑*/, '/'},
+    {'1' , 95 /*←*/ , 255 /*CTRL*/, '2', ' ', 255 /*COMODORE*/, 'q', 3 /*RUN / STOP*/},
+};
+
+unsigned char getCurrentKeyMatrixCode() {
+    return *CURRENT_KEY_MATRIX_CODE_PTR;
+}
+
+unsigned char getPreviousKeyMatrixCode() {
+    return *PEVIOUS_KEY_MATRIX_CODE_PTR;
+}
+
+unsigned char matrixCodeToPetscii(unsigned char code) {
+    char x, y;
+
+    if (code == 64)
+        return 32;
+    
+    x = code % 8;
+    y = code / 8;
+    
+    return C_64_KEYBOARD_MATRIX[y][x];
+}
+
+unsigned char getInputChar() {
+    char code = getCurrentKeyMatrixCode();
+
+    // wait until no key is pressed
+    while (code != KEY_NONE)
+    {
+        code = getCurrentKeyMatrixCode();
+    }
+    
+    // wait until key is pressed
+    while (code == KEY_NONE)
+    {
+        code = getCurrentKeyMatrixCode();
+    }
+
+    return code;
+}
diff --git a/src/input.h b/src/input.h
new file mode 100644
index 0000000..4657905
--- /dev/null
+++ b/src/input.h
@@ -0,0 +1,16 @@
+#define KEY_RETURN 1
+#define KEY_W 9
+#define KEY_S 13
+#define KEY_PLUS 40
+#define KEY_MINUS 43
+#define KEY_SPACE 60
+#define KEY_NONE 64
+
+extern unsigned short* PEVIOUS_KEY_MATRIX_CODE_PTR;
+extern unsigned short* CURRENT_KEY_MATRIX_CODE_PTR;
+extern unsigned char C_64_KEYBOARD_MATRIX[8][8];
+
+extern unsigned char getCurrentKeyMatrixCode();
+extern unsigned char getPreviousKeyMatrixCode();
+extern unsigned char matrixCodeToPetscii(unsigned char code);
+extern unsigned char getInputChar();
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..9104f49
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,358 @@
+#include <stdio.h>
+#include <conio.h>
+#include <c64.h>
+#include <string.h>
+#include <stdlib.h>
+#include "input.h"
+#include "menu/menu.h"
+
+#define DATA_ADDR 0xdd01
+#define DIR_ADDR 0xdd03
+#define SCREEN_ADDR 0x0400
+#define COLOR_ADDR 0xD800
+
+signed char NOT_STOP = 1;
+char mode = 0;
+char itr = 0;
+
+volatile char* dataPtr = (volatile char*)DATA_ADDR;
+volatile char* dirPtr = (volatile char*)DIR_ADDR;
+
+
+char* version = "0.5";
+char* creator = "Christian Werner";
+unsigned char original_background_color, original_border_color, original_text_color = 0;
+
+
+char* menu_items[] = {
+    "Output",
+    "Input"
+};
+
+char menu_items_len = sizeof(menu_items)/sizeof(menu_items[0]);
+
+char dirBuff[8];
+char dataBuff[8];
+
+char dataState = 255;
+char previousKey = 0;
+
+void writeToScreen(char x, char y, char c, char color) {
+    unsigned short offset = y * 40 + x;
+    *(char*)(SCREEN_ADDR + offset) = c;
+    *(char*)(COLOR_ADDR + offset) = color;
+}
+
+int getNumber(char* promt, int min, int max) {
+    int n;
+    printf("%s [%d-%d]: ", promt, min, max);
+    cursor(1);
+    cscanf("%d", &n);
+    cursor(0);
+
+    if (n > max) {
+        n = max;
+    }
+
+    if (n < min) {
+        n = min;
+    }
+    return n;
+}
+
+void resetScreen() {
+    clrscr();
+    textcolor(COLOR_GRAY1);
+    printf("Userport Playground v%s\ncreated by ", version);
+    textcolor(COLOR_LIGHTBLUE);
+    printf("%s\n", creator);
+    textcolor(COLOR_GRAY1);
+    chline(40);
+    textcolor(COLOR_WHITE);
+}
+
+void toBinaryArray(char *buff , char value) {
+    char mask = 1;
+    char i;
+    for(i = 0; i < 8; i++) {
+        buff[i] = value & mask;
+        value = value >> 1;
+    }
+}
+
+void drawBinary(char low, char high, char* buff, char x, char y, char c_low, char c_high) {
+    char i;
+    char c;
+    char col;
+
+    for(i = 0; i < 8; i++) {
+        if (buff[i] == 0) {
+            c = low;
+            col = c_low;
+        } else {
+            c = high;
+            col = c_high;
+        }
+        writeToScreen(x + i * 2, y, c, col);
+    }
+}
+
+void userport() {
+    char direction = *(char*)0xdd03;
+    char data = *(char*)0xdd01;
+    char key_cur, key_prev, pet_code, p_c, p_p, x, y;
+
+    toBinaryArray(dirBuff, direction);
+    toBinaryArray(dataBuff, data);
+
+    gotoxy(0,3);
+    printf("dir:  %03d  ", direction);
+    drawBinary(73+128,  79+128, dirBuff, 10, 3, COLOR_ORANGE, COLOR_GREEN);
+
+    gotoxy(0,5);
+    printf("data: %03d  ", data);
+    drawBinary(160,  160, dataBuff, 10, 5, COLOR_GRAY1, COLOR_RED);
+
+    key_cur = getCurrentKeyMatrixCode();
+    key_prev = getPreviousKeyMatrixCode();
+
+    p_c = matrixCodeToPetscii(key_cur);
+    p_p = matrixCodeToPetscii(key_prev);
+
+
+    writeToScreen(5,10, p_c, COLOR_GREEN);
+    gotoxy(7,10);
+    printf("%02d, %03d", key_cur, p_c);
+
+    x = key_cur % 8;
+    y = key_cur / 8;
+
+    printf("  %02d, %02d", x, y);
+
+}
+
+void init() {
+    original_background_color = bgcolor(COLOR_BLACK);
+    original_border_color = bordercolor(COLOR_BLACK);
+    original_text_color = textcolor(COLOR_GRAY1);
+    resetScreen();
+}
+
+int menu() {
+    char i;
+    int index;
+    resetScreen();
+    for(i = 0; i < menu_items_len; i++) {
+        printf("%d. %s\n", i+1, menu_items[i]);
+    }
+    index = getNumber("Pick mode", 1, menu_items_len) - 1;
+    return index;
+}
+
+void restore() {
+    bgcolor(original_background_color);
+    bordercolor(original_border_color);
+    textcolor(original_text_color);
+    clrscr();
+    // set char set to upper case
+    *(char*)0xd018 = 0x14;
+    *(char*)DIR_ADDR = 255;
+    *(char*)DATA_ADDR = 0;
+}
+
+void defaultLoop() {
+
+    while(1) {
+        char key = matrixCodeToPetscii(getCurrentKeyMatrixCode());
+
+        if (key == 3) {
+            mode = 2;
+            break;
+        }
+
+        if (key == 95) {
+            mode = 1;
+            break;
+        }
+
+        if (previousKey != key && key > '0' && key < '9') {
+            dataState = dataState ^ (1 << key - 49);
+            *(char*)0xdd03 = dataState;
+        }
+
+        *(char*)0xdd01 = itr;
+        userport();
+        itr++;
+        previousKey = key;
+    }
+}
+
+void fast() {
+     while(1) {
+        char key = matrixCodeToPetscii(getCurrentKeyMatrixCode());
+
+        if (key == 3) {
+            mode = 2;
+            break;
+        }
+
+        if (key == 95) {
+            mode = 0;
+            break;
+        }
+
+        if (previousKey != key && key > '0' && key < '9') {
+            dataState = dataState ^ (1 << key - 49);
+            *(char*)0xdd03 = dataState;
+        }
+
+        *(char*)0xdd01 = itr;
+        itr++;
+        previousKey = key;
+    }
+}
+
+void dod(char* title) {
+    char i = 0;
+    *(char*)0xdd03 = dataState;
+    while (1) {
+
+
+        switch (mode)
+        {
+        case 0:
+            defaultLoop();
+            break;
+        case 1:
+            fast();
+            break;
+        default:
+            mode = 0;
+            dataState = 255;
+            itr = 0;
+            return;
+        }
+    }
+}
+
+void writeAllCharsToScreen() {
+    char x, y, c;
+
+    for (y = 0; y < 7; y++) {
+        for (x = 0; x < 40; x++) {
+            c = y * 40 + x;
+            writeToScreen(x, y, c, COLOR_GREEN); 
+        }
+    }
+}
+
+void notImplemented(char* title) {
+    char origCol;
+    origCol = textcolor(COLOR_YELLOW);
+    printf("\"%s\" is not implemented :(", title);
+    textcolor(origCol);
+    printf("\nPress any key to continiue...");
+    getInputChar();
+}
+
+void exitProgram(char* title) {
+    NOT_STOP = 0;
+}
+
+
+void recieveTest(char* title) {
+    unsigned short screenStart = SCREEN_ADDR + 40 * 3 ;
+    volatile char* screen = (volatile char*)screenStart;
+    unsigned short screenEnd = SCREEN_ADDR + 40*25;
+    char d, isArduinoReady, buff;
+    char lower, upper, fullByte;
+    short i = 0;
+    lower = 16;
+    upper = 16;
+
+    *dirPtr = 0b11110000;
+    *dataPtr = 0;
+
+    while (1) {
+
+        char key = matrixCodeToPetscii(getCurrentKeyMatrixCode());
+
+        if (key == 3) {
+            break;
+        }
+
+        d = *dataPtr;
+
+        isArduinoReady = (d >> 4) & 1;
+        buff = d & 15;
+        
+        if (isArduinoReady) {
+            if (upper == 16) {
+                upper = buff;
+            } else if (lower == 16)
+            {
+                lower = buff;
+            }
+        } else {
+            continue;
+        }
+
+        if (upper != 16 && lower != 16) {
+            fullByte = (upper << 4) + lower;
+            if (fullByte > 0) {
+                *screen = fullByte;
+                screen++;
+            }
+            if (screen == screenEnd) {
+                screen = (volatile char*)screenStart;
+            }
+            upper = 16;
+            lower = 16;
+        }
+
+        //set comodore ready
+        for (i = 0; i < 100; i++) {}
+        *dataPtr = d | 0b00100000;
+
+        for (i = 0; i < 100; i++) {}
+        *dataPtr = d & 0b11011111;
+    }
+}
+
+
+void main() {
+    // int selection;
+    char huh;
+
+    Menu* menu = createMenu(4, "Main Menu", COLOR_LIGHTGREEN, 0, 3);
+    addMenuEntry(menu, "Userport Test", 0, dod);
+    addMenuEntry(menu, "Recieve Test", 1, recieveTest);
+    addMenuEntry(menu, "Test", 2, notImplemented);
+    addMenuEntry(menu, "EXIT", 3, exitProgram);
+
+    init();
+
+    while (NOT_STOP)
+    {
+        awaitMenuSelect(menu);
+    }
+    
+    //selection = menu();
+    // selection = 1;
+    // resetScreen();
+
+    // if (selection == 0) {
+    //     userport();
+    // } else {
+    //     userport();
+    // }
+
+    //*(char*)0xd018 = 0x14;
+
+    // dod();
+
+    free(menu);
+    restore();
+    exit(0);
+}
+
diff --git a/src/menu/menu.c b/src/menu/menu.c
new file mode 100644
index 0000000..aae3589
--- /dev/null
+++ b/src/menu/menu.c
@@ -0,0 +1,159 @@
+#include "menu.h"
+#include "../input.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <c64.h>
+#include <conio.h>
+
+struct MenuEntry {
+    char* name;
+    void (*callback)(char*);
+};
+
+struct Menu {
+    char* title;
+    unsigned char size;
+    short selected_index;
+    unsigned char selected_color;
+    char posX;
+    char posY;
+    MenuEntry entries[];
+};
+
+short MENU_ENTRY_SIZE = sizeof(MenuEntry);
+short MENU_SIZE = sizeof(Menu);
+
+Menu* createMenu(char size, char* title, char selected_color, char x, char y) {
+
+    Menu* menu = malloc(MENU_SIZE + size * MENU_ENTRY_SIZE);
+
+    if (!menu) return NULL;
+
+    menu->selected_index = 0;
+    menu->title = title;
+    menu->size = size;
+    menu->selected_color = selected_color;
+    menu->posX = x;
+    menu->posY = y;
+
+    return menu;
+}
+
+void addMenuEntry(Menu* menu, char* name, char index, void (*callback)(char*)) {
+    menu->entries[index].name = name;
+    menu->entries[index].callback = callback;
+}
+
+void drawMenuEntires(Menu* menu) {
+    char i;
+    MenuEntry e;
+    for (i = 1; i < menu->size + 1; i++)
+    {
+        gotoxy(menu->posX, menu->posY + i);
+        e = menu->entries[i-1];
+
+        if (i == menu->selected_index + 1) {
+            textcolor(menu->selected_color);
+            printf("%s", e.name);
+            textcolor(COLOR_WHITE);
+        } else {
+            printf("%s", e.name);
+        }
+    }
+} 
+
+void drawMenu(Menu* menu) {
+    unsigned char origtextColor;
+
+    origtextColor = textcolor(COLOR_WHITE);
+
+    gotoxy(menu->posX, menu->posY);
+    printf("[%s]", menu->title);
+
+    drawMenuEntires(menu);
+
+    gotoxy(menu->posX, 21);
+    textcolor(COLOR_GRAY1);
+    chline(40);
+    gotoxy(40 - 10, 21);
+    printf("Controls");
+    textcolor(COLOR_WHITE);
+
+    gotoxy(menu->posX, 22);
+    printf("<W>:     Up\n");
+    printf("<S>:     Down\n");
+    printf("<SPACE>: Select");
+
+    gotoxy(menu->posX, menu->posY);
+
+    textcolor(origtextColor);
+}
+
+void unDrawMenu(Menu* menu) {
+    unsigned char i;
+    for (i = 0; i < 25 - menu->posY; i++)
+    {
+        gotoxy(menu->posX, menu->posY + i);
+        cclear(40 - menu->posX);
+    }
+    gotoxy(menu->posX, menu->posY);
+}
+
+void clear() {
+    unsigned char i;
+    for (i = 3; i < 25; i++)
+    {
+        gotoxy(0, i);
+        cclear(40);
+    }
+    gotoxy(0, 3);
+}
+
+void awaitMenuSelect(Menu* menu) {
+    char current_key;
+    signed short pressedKey;
+    MenuEntry slectedEntry;
+    
+    clear();
+    drawMenu(menu);
+    pressedKey = -1;
+
+    while(1) {
+        current_key = getCurrentKeyMatrixCode();
+
+        if (pressedKey == KEY_SPACE && current_key == KEY_NONE) {
+            break;
+        }
+
+        if (pressedKey == KEY_W && current_key == KEY_NONE) {
+            
+            menu->selected_index--;
+            if (menu->selected_index < 0) {
+                menu->selected_index = menu->size -1;
+            }
+
+            drawMenuEntires(menu);
+            pressedKey = -1;
+        }
+
+        if (pressedKey == KEY_S && current_key == KEY_NONE) {
+
+            menu->selected_index++;
+            if (menu->selected_index > menu->size -1) {
+                menu->selected_index = 0;
+            }
+
+            drawMenuEntires(menu);
+            pressedKey = -1;
+        }
+
+        if (current_key != KEY_NONE) {
+            pressedKey = current_key;
+        }
+    }
+
+    unDrawMenu(menu);
+
+    slectedEntry = menu->entries[menu->selected_index];
+    slectedEntry.callback(slectedEntry.name);
+}
diff --git a/src/menu/menu.h b/src/menu/menu.h
new file mode 100644
index 0000000..9c07db0
--- /dev/null
+++ b/src/menu/menu.h
@@ -0,0 +1,7 @@
+typedef struct Menu Menu;
+typedef struct MenuEntry MenuEntry;
+
+
+extern Menu* createMenu(char size, char* title, char selected_color, char x, char y);
+extern void addMenuEntry(Menu* menu, char* name, char index, void (*callback)(char*));
+extern void awaitMenuSelect(Menu* menu);
\ No newline at end of file