Fail to access SDRAM above 1MB

Probably because there is something important at that memory location. The linker script links the program to use memory starting at 0x00100000. If you look at hwlib.axf.objdump this will become very clear. Thus you're overwriting some program code. If you want to test out alt_write_byte(), why not declare a large array global array and write to that instead. That way you can write to a safe memory location without potentially interfering with anything else.

fdh

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I am using Altera's example Altera-SoCFPGA-HardwareLib-FPGA-CV-GNU

Trying to write 1B from address 0x00100000 till 0x00200000 like:

alt_write_byte(mbs+i, (uint8_t)buf_8b[0]);

The application hangs at this point on 26th byte

Any ideas are welcome

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