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Altera_Forum
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13 years ago

Help in CRC custom instructions please.

Hello, I am a new bie in the custom instruction development for Altera and was looking into the way the CRC method is implemented as per the link altera.com/support/examples/nios2/exm-custom-...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

The busy error message is strange. Either the component isn't reset properly (do you have a correct reset signal fed to your SOPC component?) or the CPU is not reading the correct address.

For the second point, see if the system.h file in the BSP defines the correct base address for your component (it should be a# define xxx_BASE where xxx is your component name) and that it is used correctly in the code. You can also use some SignalTap probes on the component's Avalon bus to check that it is accessed correctly.