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#load "font.bin"
int drawChar(int ch, int x, int y, int color)
{
// adjust for jmp instruction
char* fontStart = 0x1FFF + 2;
int charStart = ch * 8;
for (int yOff = 0; yOff < 8; yOff++)
{
int row = fontStart[charStart + yOff];
for (int xOff = 0; xOff < 8; xOff++)
{
int bit = (row >> (7 - xOff)) & 1;
int pix = bit ? 8 : color;
setPixel(x + xOff, y + yOff, pix);
}
}
}
int setPixel(int x, int y, int c)
{
char* screenStart = 0x402F;
int i = (y * 128) + x;
screenStart[i] = c;
}
int clear(int c)
{
char* screenStart = 0x402F;
char screenSize = 64 * 128;
for (int i = 0; i < screenSize; i++)
{
screenStart[i] = c;
}
}
int getKeyState(int scanCode)
{
char* hid = 0x6033;
int index = scanCode / 8;
int bit = scanCode % 8;
int val = hid[index - 1];
return (val & (1 << bit)) != 0;
}
int print(int* text, int len, int x, int y, int color)
{
for (int i = 0; i < len; i++)
{
int ch = text[i];
drawChar(ch, x + (i * 8), y, color);
}
}
int main()
{
int x = 0;
int y = 0;
while (1)
{
for (int sk = 0; sk < 256; sk++)
{
if (getKeyState(sk))
{
while (getKeyState(sk)) { }
// Newline pressed
if (sk == 13)
{
y += 8;
x = 0;
continue;
}
// Backspace pressed
if (sk == 8)
{
x -= 8;
if (x < 0)
x = 0;
int* text = " ";
print(text, 1, x, y, 1);
continue;
}
int* text = new int[] { sk };
print(text, 1, x, y, 1);
x += 8;
}
}
if (x >= 128)
{
x = 0;
y += 8;
}
if (y >= 64)
{
x = 0;
y = 0;
clear(8);
}
}
}
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