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Elite on the BBC Micro

Maths (Arithmetic): MLU2 [Cassette version]

Name: MLU2 [Show more] Type: Subroutine Category: Maths (Arithmetic) Summary: Calculate (A P) = |A| * Q
Context: See this subroutine in context in the source code References: This subroutine is called as follows: * STARS1 calls MLU2 * STARS6 calls MLU2

Do the following multiplication of a sign-magnitude 8-bit number P with an unsigned number Q: (A P) = |A| * Q
.MLU2 AND #%01111111 \ Clear the sign bit in P, so P = |A| STA P \ Fall through into MULTU to calculate: \ \ (A P) = P * Q \ = |A| * Q