#define atari_width 17
#define atari_height 14
-static char atari_bits[] = {
+static unsigned char atari_bits[] = {
0x30,0x00,0x00,0x4a,0x00,0x00,0x80,0x00,0x00,0x09,0x01,0x00,0xc4,0x07,0x00,
0xc0,0x07,0x00,0xf0,0x1f,0x00,0xf8,0x3f,0x00,0xd8,0x3f,0x00,0xfc,0x7f,0x00,
0xfc,0x7b,0x00,0xf8,0x3b,0x00,0xf8,0x3d,0x00,0xf0,0x1f,0x00};