Some issue on FT2232H in Synchronous FIFO

Altera_Forum · ‎01-13-2016

Hello everyone!

I have some troubles with the FTDI chip.

I use it in this way: FPGA+FT2232H on custom board and PC Application on the other side. All stuff using in Synchronous FIFO mode. So from now I’m trying to send a byte command from FPGA and catch it in the windows application. And here is the problem. I didn’t saw errors or warnings it just not working. Maybe someone have the same problem as I have.

Well here is my VHDL code in the key of write operation(all ports have the same name as in the datasheet):

WRITE_STR: process (CLK, TXE, RST)    begin
    if (RST = '0' OR RD_CONTROL <= "00") then
        WR_CONTROL <= '1'; 
        data_tx <= "00000000";
    elsif ((CLK'EVENT) and (CLK='1')) then
        if (TXE = '0' and RD_CONTROL <= "11") then
            WR_CONTROL <= '0';
            data_tx <= "01101011";
        else
            WR_CONTROL <= '1';
        end if;
    end if;
    WR <= WR_CONTROL;
    ADBUS <= data_tx;
    
end process WRITE_STR;

And it is simulating right as I see (pic 01.jpg).

PC application. I use Visual C# 2010 i'm a new one here, so.

Here is the settings after the chip is opened:

  
            ftStatus = myFtdiDevice.SetBitMode(0x00, FTDI.FT_BIT_MODES.FT_BIT_MODE_RESET);            
            Thread.Sleep(10);
            ftStatus = myFtdiDevice.SetBitMode(0xFF, FTDI.FT_BIT_MODES.FT_BIT_MODE_SYNC_FIFO);        
            if (ftStatus != FTDI.FT_STATUS.FT_OK)
                return false;
            
            ftStatus = myFtdiDevice.SetLatency(0x10);
            ftStatus = myFtdiDevice.InTransferSize(10000); 
            ftStatus = myFtdiDevice.SetTimeouts(0, 0);
            ftStatus = myFtdiDevice.SetFlowControl(FTDI.FT_FLOW_CONTROL.FT_FLOW_RTS_CTS, 0x0, 0x0);
            ftStatus = myFtdiDevice.Purge(FTDI.FT_PURGE.FT_PURGE_RX);
            Thread.Sleep(10);

I'll trying to change Flow Control to 0x11, 0x13 nothing happened. Change TheTransferSize and TimeOuts still the same.

Here writting code by clicking on button, app must read one byte:


        private void button1_Click_1(object sender, EventArgs e)
        {
            FTDI.FT_STATUS ftStatus = FTDI.FT_STATUS.FT_OK;
            UInt32 RxBytes = 0;
            myFtdiDevice.GetRxBytesAvailable(ref RxBytes);
            if (ftStatus != FTDI.FT_STATUS.FT_OK) {
                textBox2.Text += "FTDI.GetRxBytesAvailable failed";
                return;
            }
            Byte ByteRead = new Byte;
            UInt32 BytesRead = 0;
            myFtdiDevice.Read(ByteRead, RxBytes, ref BytesRead);
            if (ftStatus != FTDI.FT_STATUS.FT_OK)
            {
                textBox2.Text += "FTDI.Read failed";
                return;
            }
            else {
                textBox2.Text += "Reading data is " + Encoding.UTF8.GetString(btRead) + " from FPGA" + Environment.NewLine; // well, for example
            
            }

In the other hand if i use terminal in the Morph-IC-II Application after the FPGA is will be programmed and USB cable already plug in you can see pic 02.jpg.

Can someone explane to me how does this happen?

Altera_Forum · ‎01-13-2016

Check TXE and RXF on either edge, not only on rising edge

http://electro-logic.blogspot.it/2014/03/fpga-comunicazione-ad-alta-velocita_1.html

Altera_Forum · ‎01-13-2016

--- Quote Start ---

Check TXE and RXF on either edge, not only on rising edge

http://electro-logic.blogspot.it/2014/03/fpga-comunicazione-ad-alta-velocita_1.html

--- Quote End ---

Can you explain more about it?

I didn't get

Altera_Forum · ‎01-14-2016

Example:

if ((CLK'EVENT) and (CLK='1')) then

if (TXE = '0') ...

end if

shoud became

if (TXE = '0') ...

read the article..