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Altera_Forum's avatar
Altera_Forum
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14 years ago

configuration device

Hello. I am new to FPFA world and i am trying to understand whats is AP mode and AS mode in cyclone4 ? How i set this mode with hardware or software and witch mode i will need for ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

AS and AP mode refer to the type of flash device used for configuration. As the FPGA has only SRAM, you need a flash to store it's configuration, that will be downloaded during power up. AP refers to a parallel flash and AS to a serial one. AP mode is faster but requires more pins from the FPGA. IF you also use the flash from software, both type can also be used. With a parallel Flash you can execute the code directly from the flash, whereas with a serial one you need a bootloader that will copy the application into RAM.