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Altera_Forum
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13 years ago

.rwdata and .bss do not work with custom memory controller

Hi, I have designed a custom SRAM memory controller connected to a NIOS II processor that - as far as I can see - works. Running a test program from on-chip memory, reading/writing happens with...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

The other byte-enable 'GOTCHA' happens when using the PCIe to Avalon bridge - a PCIe cycle writing to a 32bit item ends up generating 2 bus cycles, the second of which has no byte enables asserted!

So even though you only expect 32bit accesses you still need to look at (at least one of) the byte enables.