Notation
The "h" in Mode 13h stands for "hexadecimal"; it is actually VGA mode 19 in decimal. In x86 assembly language the mode is entered when AL is 13h, AH is 0 and BIOS INT 10h is executed. However, the "h" is sometimes dropped for languages that don't support that method of notation; for example, it is known as screen mode 13 in QuickBasic and its spinoffs. In C, hexadecimal 13 is written 0x13.
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