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Altera_Forum
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15 years ago

Code in tightly coupled memory

Hi all, I placed a function in a section different from the main code. More exactly, my code is mapped to sdram and I linked a function testcall() into a tightly coupled memory section which I pr...
Altera_Forum's avatar
Altera_Forum
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15 years ago

Cris, I use the function in TCM to cyclical control and setup SGDMA descriptors. Data from a sensor must be copied in limited time to SDRAM. If I allow IRQs then I don't receive all the data from sensor. In this time any other master access on the SDRAM leads to loss of data.

Furthermore I use global variables for that function because stack and heap are in SDRAM.

I mean functionality should not affected if IRQs allowed or not but I couldn't test it.

An other effect I had in conjunction with dual port RAM. First I put TCM and descriptors together in one dual port RAM. In this case I also had loss of data.

How do you create the tc_code section? The TCM section I'm using has the same name like the SOPC component (onchip_ram). This naming has effects to the generated linker script. If you will use additional sections than you have to provide a custom linker script.

Jens