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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
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13 years ago

Yeah! I took a long time to fix those. Google search did not help much.

Now I am able to build the application code for CRC HW in my NIOS II IDE, however issues pop up when I run the code.

Error: Attempting to start the checksum accelerator while it is busy... exiting

Is the error that I get while running the code.

I have tried to build an SOPC system that looks like the sopc system given in the CRC example, did the SOPC and the Quartus II build and then did the NIOS II IDE build.

I see in the application code that for the hardware checksum they are registering an ISR. Was wondering these will work or not if I do not have a proper SOPC system.

As of now the code is getting issues while it calls the following function: write_to_add_len_ctrl_registers()

Thank You,

Akhil