In computer processors the carry flag (usually indicated as the C flag) is a single bit in a system status (flag) register used to indicate when an arithmetic carry or borrow has been generated out of the most significant ALU bit position. The carry flag enables numbers larger than a single ALU width to be added/subtracted by carrying (adding) a binary digit from a partial addition/subtraction to the least significant bit position of a more significant word. It is also used to extend bit shifts and rotates in a similar manner on many processors (sometimes done via a dedicated X flag). For subtractive operations, two (opposite) conventions are employed as most machines sets the carry flag on borrow while some machines (such as the 6502 and the PIC) instead resets the carry flag on borrow (and vice versa).
Read more about Carry Flag: Uses, Carry Flag Vs. Borrow Flag
Famous quotes containing the words carry and/or flag:
“Here may I not ask you to carry those inscriptions that now hang on the walls into your homes, into the schools of your city, into all of your great institutions where children are gathered, and teach them that the eye of the young and the old should look upon that flag as one of the familiar glories of every American?”
—Benjamin Harrison (1833–1901)
“Our flag is red, white and blue, but our nation is a rainbow—red, yellow, brown, black and white—and we’re all precious in God’s sight.”
—Jesse Jackson (b. 1941)