mirror of https://github.com/hsoft/collapseos.git
17 lines
539 B
Plaintext
17 lines
539 B
Plaintext
Structured flow
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z80a also has words that behave similarly to IF..THEN and
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BEGIN..UNTIL.
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On the IF side, we have IFZ, IFNZ, IFC, IFNC, and THEN,. When
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the opposite condition is met, a relative jump is made to
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THEN,'s PC. For example, if you have IFZ, a jump is made when
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Z is unset.
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On the BEGIN,..AGAIN, side, it's a bit different. You start
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with your BEGIN, instruction, and then later you issue a
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JRxx, instr followed by AGAIN,. Exactly like you would do
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with a label.
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(cont.)
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