OTDR |
Block output with decrement. | |||||||||
| Function: | (C)
(HL); B
B - 1; HL
HL - 1Repeat until B = 0 |
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| Format: |
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byte 1: ED |
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byte 2: BB |
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| Description: | The contents of the memory location addressed by the HL register pair are output to the peripheral device addressed by the contents of the C register. Both the B register and the HL register pair are then decremented. If B  0, the program counter is decremented by 2 and the instruction is re-executed. C supplies bits A0 to A7 of the address bus. B supplies (after decrementation) bits A8 to A15. |
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| Data Flow: | ||||||||||
| Timing: | B = 0: 4 M cycles; 16 T states: 8 usec @ 2 MHz B 0: 5 M cycles; 21 T states: 10.5 usec @ 2 MHz |
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| Addressing Mode: | external |
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| Flags: | ||||||||||
| Example: | OTDR |
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OBJECT CODE |
Before: |
After: |
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