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Author Topic: Reading EEPROM memory with FT4222H bridge  (Read 801 times)


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Reading EEPROM memory with FT4222H bridge
« on: October 02, 2020, 10:28:50 AM »

I would like to read an EEPROM Memory (SPI Flash Winbond) using an FTDI USB/SPI bridge (FT4222H). I developed a c++ application that connects to the FTDI and reads data from the memory(and using the FTDI library). I am using the continuous mode read because it's much faster than the buffer read. The problem is that the FTDI transfer limit is 64Kbytes and the total memory is 256MBytes so I have to read 64Kbyte in a loop of 4096 times and then save it in a file. The problem is that each time you have to send the OpCode of reading memory followed by 7 Dummy Bytes, which I lost each time 8Bytes in each 64Kbyte.

I tried to read less then 64Kbye (for example 60Kbyte +8Byte) but I realize that the data was corrupted and is not properly read. Also, I tried to fix the starting reading page in each 60Kbyte but the same, the data was corrupted.

Does anyone have an Idea about that or he reads data through an FT4222H bridge?

And Thank you very much :)

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Re: Reading EEPROM memory with FT4222H bridge
« Reply #1 on: October 05, 2020, 04:40:19 PM »


We will need some additional information in order to help you on this issue:

1.            What is the winbond spi flash model number?
2.            What is the operating IO mode (single/dual/quad)?
3.            Can you request provide your source code?

Please send us an email with this information:


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