Description For the PFL megafunction created with the Quartus® II software version 6.0, the flash_addr and flash_data buses are not tri-stated, but driving out unspecified signals when the megafunction is not accessing the flash device. If there is another device that needs to access the flash, then you will need to tri-state the buses accordingly. You can do so by using the pfl_flash_access_request signal as a control signal. The PFL drives this signal high when it needs to access the flash.
MicroBlaster™ Fast Passive Parallel Software Driver
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