20 lines
543 B
ArmAsm
20 lines
543 B
ArmAsm
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select_device:
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// Take last device number, make sure it's a drive - 8 or above. Above 30,
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// although illegal for IEC we also consider a drive, as they exists
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// drivers assigning these numbers to CBM-DOS capable devices - like some
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// IEEE-488 carts.
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//
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// If current device is not a drive, set device to 8 (first drive number)
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// Device number is left in X, for SETFLS Kernal routine
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// Note: if tape support is introduced here, make sure DOS wedge won't get broken
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ldx current_device_number
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cpx #$08
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bcs !+
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ldx #$08
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!:
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rts
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