Routines
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B6B2: Compare Scores
Used by the routines at NewHighScore and NewHighScore_Enter.
Compares the scores pointed to by DE and HL. They are held as three bytes, with the most significant digits first.
Input
DE Pointer to a score
HL Pointer to a score
Output
F Carry set if the score at DE is less than the score at HL. Zero set if they are equal
NewHighScore_Compare B6B2 PUSH BC Stash BC, DE and HL on the stack.
B6B3 PUSH DE
B6B4 PUSH HL
Scores are held in three bytes.
B6B5 LD B,$03 Set the number of bytes of the score in B to 03.
NewHighScore_Compare_Loop B6B7 LD A,(DE) Fetch a pair of digits of the first score.
B6B8 CP (HL) Compare it with the pair of digits of the second score.
B6B9 JR C,NewHighScore_Compare_Return Jump to NewHighScore_Compare_Return if the first score is lower.
B6BB JR NZ,NewHighScore_Compare_Return Jump to NewHighScore_Compare_Return if the first score is higher.
B6BD INC HL Move onto the next pair of digits of both scores.
B6BE INC DE
B6BF DJNZ NewHighScore_Compare_Loop Decrease the digit pair counter by one and loop back to NewHighScore_Compare_Loop until all three pairs of digits have been compared.
NewHighScore_Compare_Return B6C1 POP HL Restore HL, DE and BC from the stack.
B6C2 POP DE
B6C3 POP BC
B6C4 RET Return.
View the equivalent code in;
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