FTDI FT245RL problem

[STU_KNTU]

hi every one.
I want to transmit data from spartan 3 to computer via usb port with FT245Rl.
but i am some problem when i'm sending data to computer.
I've write a code in fpga side that sends 0 then 1 until 255 and then 0 again and ..... constantly.
and also i've write a code in D2xx mode that when code detect 0 start to saving data until it get to 255.
but here is the problem
in computer side i dont receive correct data.
for example i receive 1,2,5,5,7,8,9,10,10,12 and .....
could you tell me whats wrong about this project and which part could be probably wrong???:bang:

 

[FvM]

You're apparently ignoring the concept of FIFO handshaking yet.

 

[STU_KNTU]

thanks for your response.
.So how can i solve it ?? any idea ??
Im really need to connect to pc.

 

[FvM]

As already mentioned, use handshake signals on the 245 interface and read the data as a stream on the PC side.

FT245 has different FIFO handshake modes, review the datasheet to find out which one is appropriate for your application.

 

[STU_KNTU]

do you mean wr,rd,txe and rxf ???
when txe is low i put data in D0...D7 and then active wr
interesting point that when im changing the buad rate with ft_set_buadrate in C++
the data i receive changes.
for example when buadrate is 45000 the receiving :1,2,5,5,7,9 and ...
but when set this to 60000 data is like this :1,1,2,2,3,4,4,5,5,7,8,8

 

[FvM]

You didn't yet tell what you are exactly doing. I would expect one write pulse for each data value, respectively you'll receive each value only once in the stream read on the PC side.

Baud rate has no meaning for a parallel FIFO interface.

 

[STU_KNTU]

I exactly do same thing.the period of write cycle is 400khz also
So why when I change buad rate the stream of receving data changes also??
Do you think the problem is on pc side ??can I put my code here??

 

[FvM]

You definitely should.

 

[KlausST]

Hi,

And best a wiring diagram...and scope pictures of Wr and Txe (dual channel)
If you have a third channel, then show D0 also.

Klaus

 

[STU_KNTU]

here you are ::thumbsup:

#include "stdafx.h"
#include <Windows.h>
#include <conio.h>
#include <iostream>
#include <fstream>
#include <string>
#include "ftd2xx.h"
#include <time.h>

using namespace std;

int * binary(int);
//void usleep(__int64);

int main(void)
{
	FT_HANDLE ftHandle;
	FT_STATUS ftstatus;
	ftstatus = FT_Open(0, &ftHandle);
	if (ftstatus != FT_OK){
		cout << "Opening failed!" << endl;
		int a;
		cin >> a;
		return 1;
	}
	else
		cout << "FT Open sucssesfull" << endl;

	//Set Baud Rate
	ftstatus = FT_SetBaudRate(ftHandle, 49000);
	if (ftstatus == FT_OK)
		cout << "FT_SetBaudRate:  OK!" << endl;
	else
		cout << "FT_SetBaudRate:  FAILED!" << endl;
	//Data Characteristics
	FT_SetDataCharacteristics(ftHandle, FT_BITS_8, FT_STOP_BITS_1, FT_PARITY_NONE);
	FT_SetFlowControl(ftHandle, FT_FLOW_NONE, 0, 0);
	////////////////////////////////////////////////////////////////////
	int number = 0;
	int bit = 0;
	unsigned char CntrlSig[1];
	int FileNum = 0;
	unsigned char TST[2];
	unsigned int temp1 = 0;
	unsigned char RX[7296];
	/////////////////////////////////////////////////////////////////////////
	while (number != -1 || bit != -1){
		bool bitistrue = false;
		cout << "Please enter 0 or 1: ";
		while (bitistrue == false)
		{
			cin >> bit;
			if (bit == 0 || bit == 1)
				bitistrue = true;
			else
				cout << "Wrong number " << endl;
		}
		////////////////////////////////////////////////////////////////////
		cout << "Please enter a positive integer between 0 and 127: ";
		bool numberistrue = false;
		while (numberistrue == false)
		{
			cin >> number;
			if (number < 0 || number > 127)
				cout << "That is not a valid number" << endl;
			else
				numberistrue = true;
		}
		/////////////////////////////////////////////////////////////////////
		FileNum++;
		string FileName = "TCD_Data" + to_string(FileNum) + ".dat";
		cout << "File Name is : ";
		cout << FileName << endl;
		int tmp = bit * pow(2, 7) + binary(number)[6] * pow(2, 6)
			+ binary(number)[5] * pow(2, 5) + binary(number)[4] * pow(2, 4)
			+ binary(number)[3] * pow(2, 3) + binary(number)[2] * pow(2, 2)
			+ binary(number)[1] * 2 + binary(number)[0];
		CntrlSig[0] = (unsigned char)tmp;
		cout << "Control Byte is :";
		cout << tmp << endl;
		////////////////////////////////////////////////////////////////
		//Set Asynchronous Bit-bang Mode
		UCHAR Mask = 0xff;//set all pins output
		UCHAR mode = 0x1;//Set asynchronous bit-bang mode
		ftstatus = FT_SetBitMode(ftHandle, Mask, mode);
		if (ftstatus == FT_OK)
			cout << "ALL Pins output : OK! " << endl;
		else
			cout << "ALL Pins output : FAILED!" << endl;
		////////////////////////////////////////////////////////////////
		DWORD BytesWritten;
		DWORD EventDWord_wr;
		DWORD Txbytes_wr;
		DWORD RxBytes_wr;
		FT_GetStatus(ftHandle, &RxBytes_wr, &Txbytes_wr, &EventDWord_wr);
		cout << "RxBytes_wr is :";
		cout << RxBytes_wr << endl;
		cout << "TxBytes_wr is :";
		cout << Txbytes_wr << endl;
		ftstatus = FT_Write(ftHandle, CntrlSig, 1, &BytesWritten);
		if (ftstatus == FT_OK)
			cout << "FT_Write OK" << endl;
		else
			cout << "FT_Write Failed" << endl;
		////////////////////////////////////////////////////////////////
		//Set Asynchronous Bit-bang Mode
		Mask = 0x00;//set all pins input
		ftstatus = FT_SetBitMode(ftHandle, Mask, mode);
		if (ftstatus == FT_OK)
			cout << "ALL Pins input : OK! " << endl;
		else
			cout << "ALL Pins input : Failed!" << endl;
		////////////////////////////////////////////////////////////////
		DWORD EventDWord;
		DWORD Txbytes;
		DWORD RxBytes;
		DWORD BytesReceived;

		//int wait = (number + 1) * 125 * 2.4 + 800;
		//usleep(wait);
		bool chkRead = false;
		bool chkFile = false;
		//FOR WRITE TO FILE IF DATA IS VALID
		if (bit == 1){
			bool zeroisone = false;
			bool oneisone = false;
			while (zeroisone == false || oneisone == false){
				FT_GetStatus(ftHandle, &RxBytes, &Txbytes, &EventDWord);
				if (&RxBytes > 0){
					ftstatus = FT_Read(ftHandle, TST, 2, &BytesReceived);
				}
				if ((unsigned int)TST[0] == 1)
					zeroisone = true;
				else
					zeroisone = false;
				if ((unsigned int)TST[1] == 1)
					oneisone = true;
				else
					oneisone = false;
			}
			//////////////////---/-/-/-/--/-/-/-/--/////////////////////////////
			///Event_Read
			HANDLE hEvent;
			DWORD EventMask;
			hEvent = CreateEvent(NULL, false, false, NULL);
			EventMask = FT_EVENT_RXCHAR;
			DWORD EventDWord;
			DWORD Status;
			int y = 0;
			while (1){
				ftstatus = FT_SetEventNotification(ftHandle, EventMask, hEvent);
				WaitForSingleObject(hEvent, INFINITE);
				FT_GetStatus(ftHandle, &RxBytes, &Txbytes, &EventDWord);
				if (RxBytes > 0) {
					ftstatus = FT_Read(ftHandle, &RX[y], 1, &BytesReceived);
					if (ftstatus == FT_OK)
						y++;
					cout << y << endl;
					if (y == 200){
						y = 0;
						break;
					}
				}
			}
			///////////////-/-/--/-/-/////////////-------///////////////////////
			cout << "Protocol Bytes Recived" << endl;
			if (zeroisone == true && oneisone == true){
				FT_GetStatus(ftHandle, &RxBytes, &Txbytes, &EventDWord);
				cout << "RxBytes is :";
				cout << RxBytes << endl;
				cout << "TxBytes is :";
				cout << Txbytes << endl;
				/*if (&RxBytes > 0){
				ftstatus = FT_Read(ftHandle, RX, 7296, &BytesReceived);
				if (ftstatus == FT_OK){// && chkRead == false){
				cout << "FT_Read OK" << endl;
				//chkRead = true;
				}
				else if (ftstatus != FT_OK){
				cout << "FT_Read Failed" << endl;
				//chkRead = false;
				}
				}*/


				// open a file in write mode.
				ofstream outfile;
				outfile.open(FileName, ios::out);
				for (int i = 0; i < 7296; i++){
					//if (i % 2 == 0){
					temp1 = (unsigned int)RX[i];
					//}
					//else if (i % 2 == 1){
					//temp1 = temp1 << 8;
					//temp1 = temp1 + (unsigned int)RX[i];
					outfile << temp1 << endl;
					//}
				}// FOR
				outfile.close();
			}//WHILE ONEISONE .. IS FALSE
		}// if (bit==1)

		else if (bit == 0){
			unsigned char TST100[2];
			unsigned char RX[100][7296];
			unsigned int temp2 = 0;
			bool zeroisone100 = false;
			bool oneisone100 = false;
			// open a file in write mode.
			ofstream outfile;
			outfile.open(FileName, ios::out);
			for (int i = 0; i < 100; i++)
			{
				bool chkRead100 = false;
				bool chkFile100 = false;
				while (zeroisone100 == false || oneisone100 == false){
					FT_GetStatus(ftHandle, &RxBytes, &Txbytes, &EventDWord);
					if (&RxBytes > 0){
						ftstatus = FT_Read(ftHandle, TST100, 2, &BytesReceived);
					}
					if ((unsigned int)TST100[0] == 254)
						zeroisone100 = true;
					else
						zeroisone100 = false;
					if ((unsigned int)TST100[1] == 254)
						oneisone100 = true;
					else
						oneisone100 = false;
					zeroisone100 = true;
					oneisone100 = true;
				}
				if (zeroisone100 == true && oneisone100 == true){
					cout << "Protocol Bytes Recived" << endl;
					FT_GetStatus(ftHandle, &RxBytes, &Txbytes, &EventDWord);
					if (&RxBytes > 0){
						ftstatus = FT_Read(ftHandle, RX[i], 7296, &BytesReceived);
						if (ftstatus == FT_OK){// && chkRead100 == false){
							cout << "FT_Read OK" << endl;
							//chkRead100 = true;
						}
						else if (ftstatus != FT_OK){
							cout << "FT_Read Failed" << endl;
							//chkRead100 = false;
						}
					}
					for (int h = 0; h < 7296; h++){
						// if (chkFile100 == false){
						//cout << "Cannot Read! Data Not Received!!!" << endl;
						//chkFile100 = true;
						//}
						if (h % 2 == 0){
							temp1 = (unsigned int)RX[i][h];
						}
						else if (h % 2 == 1){
							temp1 = temp1 << 8;
							temp1 = temp1 + (unsigned int)RX[i][h];
							outfile << temp1 << endl;
						}
					}// FOR
					outfile << "			**************	End of Data	**************";
				}//WHILE ONEISONE .. IS FALSE
			}//for 100
			outfile.close();
		}//end if (bit = 0)
	}//while!=-1
	return 0;
}







int * binary(int number)
{
	int remainder;
	int bi[8];
	for (int i = 0; i < 8; i++)
	{
		remainder = number % 2;
		number = (number >> 1);
		bi[i] = remainder;
	}
	return bi;
}

and also handshaking wires :

 

[KlausST]

Hi,

your diagram is simulation only. We need real scope pictures.

In the diagram we don´t see the short "high" cycling of the TxE signal after the WR signal.
Also we don´t see what´s happening in case the fifo is full. ie when Txe is high for an undefined time.

Klaus

 

[STU_KNTU]

i agree but i havent any scope to take pictures .
i can put my vhdl code here.is this enough??
as mentioned in picture when txf is high fpga wont write on ft.

entity test1 is
port( 	Rxf,Txf	:	In  	std_logic;
			Wr,Rd		:	out 	std_logic:='0';
			data		:	inout	std_logic_vector(7 downto 0):="00000000";
			Clk		:	in		std_logic;--50 mhz
			lamp		:	out	std_logic
		);
end test1;
--/////////////////////////////////////////////
architecture Behavioral of test1 is
signal Counter	:	std_logic_vector(7 downto 0) :=(others => '0');
signal state	:	std_logic_vector(1 downto 0):="00";
begin
Counter <= Counter + '1' when clk'event and clk = '1';
Rd <= '1';
lamp <= '0';
process(Counter(7))
begin
If Counter(7)'event and Counter(7) = '1' then
Case State is
when "00" =>
	If Txf = '0' then 
		state <= state + "01";
		data <= data + "00000001";
		end if;
when "01" =>
	Wr <= '1' ;	
	state <= "10";
when "10" =>
	Wr <= '0';
	state <="00";
when others => 
state <= "00";
end case;
end if;
end process;

 

[FvM]

In terms of FPGA design guidelines, it's a bad example of using a generated clock instead of a clock enable signal. But that's not causing problems for this simple design, it looks like you are sending a stream with exactly one sample per value to the FIFO. So the problem is probably with the receiver code.

 

[STU_KNTU]

thanks.so whats wrong with receiver code???
do you realized something??

 

[FvM]

Apparently the interface is operated asynchronously instead of reading from the FIFO.

 

[KlausST]

Hi,

don´t use any bitbang mode.
to be on the safe side you could reset the bitbang mode:

***
To reset the IO bit mode:
ftStatus = FT_SetBitMode(ftHandle,0,0);
***

Klaus

 

[STU_KNTU]

thanks alot.i have little problems.:sad:

don´t use any bitbang mode.

Apparently the interface is operated asynchronously instead of reading from the FIFO.

so what mode i must use after i reset the Ft?
in data sheet this modes declared...

 

[KlausST]

Hi,

What information do you need?

so what mode i must use after i reset the Ft?

Nothing. Keep it simple. Start your transmission.
(You don´t reset the "FT". You reset "bitbang mode" and automatically operate in normal mode)

Maybe best is NOT to use SetBitMode at all.

Klaus