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Altera_Forum
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16 years ago

Problem accessing RAM-memory

Hi all, I'm trying to access a dualport RAM-unit. It's purpose is to act like a FIFO-buffer. Addresses are written to incremently. Thus, the code I'm using looks like: ram_64_15_write_addr...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

@Daixiwen: yes, the process is triggered by a clock.

@okerol: I have also tried to use an incrementing std_logic_vector, which had thesame behavior: working simulation but malfunctioning real-life behavior.

I have solved the problem by not using an address at all: I have used the FIFO-megafunction of Quartus and it's working now.

I was using a self-written RAM-function first, then when that didn't work I tried the RAM-megafunction of Quartus. That showed thesame false behavior.

For the ones that are interested: In the attachment file I have supplied the interesting piece of code from my file. Also an image file from the signaltap is included which shows the signal 'schrijfadres' (the discussed variable I changed to 'specific_address' for this post) isn't changing at all! Only the least significant bit is changing. Again: in simulation, it works as planned.