Hi,
I am working on slave FIFO intereface for FX2LP usb controller. I am configuring the FIFO in auto mode.
Once the master gives the 8bit data to the slave FIFO bus (FD0-FD7), I am expecting the data to be commited to the USB endpoint buffer with the following code segment :
I am using EP2 as bulk in endpoint and I am disabling all other endpoints
SYNCDELAY; //
EP2CFG = 0xE0; // bulk endpoint and quad buffering
SYNCDELAY; //
EP6CFG &= 0x7F; //clear valid bit
SYNCDELAY;
EP4CFG &= 0x7F; // clear valid bit
SYNCDELAY; //
EP8CFG &= 0x7F; // clear valid bit
SYNCDELAY;
FIFORESET = 0x80; // activate NAK-ALL to avoid race conditions
SYNCDELAY; // see TRM section 15.14
FIFORESET = 0x02; // reset, FIFO 2
SYNCDELAY; //
FIFORESET = 0x04; // reset, FIFO 4
SYNCDELAY; //
FIFORESET = 0x06; // reset, FIFO 6
SYNCDELAY; //
FIFORESET = 0x08; // reset, FIFO 8
SYNCDELAY; //
FIFORESET = 0x00; // deactivate NAK-ALL
SYNCDELAY; //
EP2FIFOCFG = 0x08; // AUTOIN=1, WORDWIDE=0
SYNCDELAY; //
I am also configuring the buffer length as 512bytes as below:
EP2AUTOINLENH = 0x02;
SYNCDELAY;
EP2AUTOINLENL = 0x00;
SYNCDELAY;
Is this all required for passing the 8bit FIFO data from master to USB host. ? Can I read the data from master using any dotnet application as mentioned below :
len = 512;
byte[] buffer = new byte[len]
ret = myDevice.BulkInEndPt.XferData(ref buffer, ref len, false);
Since the master gives 8bit data, I am grounding the FD[8] to FD[15] lines through 10K resistor. So, should I explicitly disable the PORTD pins.
In my case, I am interfacing an 8bit cmos camera. As soon as I download the code into FX2LP RAM, the signal strength from the camera is getting too low so that I am getting a black image data as soon as I try to read the USB data from the dotnet appplication.
And also even though the FD8 to FD15 lines are grounded, I get a high voltage lvel on some of these lines.
Why are the are the camera interface lines getting low as soon as I start running the code ? And also, Why am I observing a voltage level on FD8 to FD15 lines even though it remains grounded ?
Thank You
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