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Altera_Forum
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11 years ago

Nios and tcl script writing to RAM

Hi, I have an image loaded with a Nios , Jtag master and jtag UART. I have wrote C code to write to the on-chip RAM. I have also a tcl script that can read and write to the RAM. When ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

Hi Dave,

The processor is using the on-chip memory and I am writing to off-chip DDR3.

I have taken your bemicro_cv ddr example that you gave me before and adapted it for my board. I have checked it again and now it works as expected.

The issue however is that I had cloned it into another separate project and removed the LED control from the Qsys and removed other ports from the top-level file such as for the MicroSD and I2C ports. I did this in order to make the design as simple as possible with just a DDR3 controller and Nios. Only when I do this, tcl and C are giving different values. If I reload the other image with everything included, I am reading the correct values again across C and tcl.

This I find strange. If the tcl read command is showing the same value that I wrote using tcl, doesn't this mean that it is working fine anyways? I am wondering why by just removing the LED output and other unused ports from that project that I don't read the same values written with C from tcl and vice versa but write and read using only C or only tcl reads back the correct values. ))

Thanks,

Paul