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Altera_Forum
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15 years ago

Why is the maximum burst count 2 ** (AV_BURSTCOUNT_W-1)

In altera_avalon_mm_master_bfm, when the burst count is greater than 2 ** (AV_BURSTCOUNT_W-1), it will generate a warning. Suppose AV_BURSTCOUNT_W is 4, then the maximum burst count is 15 instead of ...
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Altera_Forum
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15 years ago

The maximum burst count is 2**(N-1) because that is what Altera defined it to be in the avalon interface specifications (http://www.altera.com/literature/manual/mnl_avalon_spec.pdf).

This definition is somewhat arbitrary. I would guess Altera chose 2**(N-1) instead of (2**N) - 1 so that the max burst count is an even power of 2.

To guarantee compatibility between components, you need to adhere to the specification.