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Altera_Forum's avatar
Altera_Forum
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18 years ago

User Flash Memory Simulation in Quartus II

Hi all,

My device is EPM570T100C5. In Quartus II, i use UFM. All settings are below:

SPI interface portocol

Read/Write

Base mode

no .mif file

5.56MHz osc(for simulation)

500,000 ns erase time(for simulation)

1,600 ns program time(for simulation)

In the Waveform file, i input 2 data. The first data is at the time of 10us and the second at 730us. For the first data, the UFM can erase, write and read correctly.

But the second data can not write into the UFM, though in the Write Step, the waveform of opcode, address and data is right in simulation report. The Erase Step cost just about 10us(not 500us which i set) and the Write Step cost a long time(about 500us). When reading, the output is all 1s. It seems that after erasing, the Read Step is following.

Why?Is there any requirement between two Erase Steps?Or, someting wrong during simulation?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    18 years ago

    From my experience with the SPI megafunction, it works fine. Some of the things you might want to check:

    1. Write enabled for the UFM (with the instructions)

    2. Whether the block is write-protected (by reading back the status register data)

    You can also check the nRDY bit and see if the erase or programming is happening. If erase or programming is happening, you should wait until the process is completed.

    Hope this helps.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    18 years ago

    Thanks.

    I use RDSR Step to find out whether the nRDY is busy.

    Because the interface is powered-up in the write disable state, i set WREN when the nRDY is not busy. Then, i set BP0 & BP1 zero before going to ERASE STEP. After the erase opcode, i use RDSR again to check out the erase step completed and then step into WRITE STEP.

    I think that's it.

    Yesterday, i use Parallel interface to control the UFM, it works well:)