Generating UCF file for the UART module

[Smith]

Hi all.
I am now trying to test my UART module with using the Spartan 3 board.
As in the UART module, for the submodule of the receiver, I have 8 bit
data to feed the Receive port which is the P3 in the Spartan 3. In the
other hand, the transmit port for the 8 bit data to be transmitted is
via the P4 port in the Spartan 3.

When I want to generate the UCF file, my problem comes. In the list of
I/O pins, there are the receive port (input) and following by bit 0 to
7 input. Besides, for the output, it starts with bit 7 down to the bit
0 and then followed by the output port which is the transmitt port for
the submodule transmitter. I have no problem in assigning the port for
the clock as it only one.

My doubt is does it need to assign each bit of the data to the specific
port, either the receiver module or the transmitter module? I had tried
to assign all the bits to the same port, but it seems it only able to
assign the receive port to the P3 and bit 7 of the data in the
transmitter module for P4. Did I make any mistake in this? Or only i
need is just to assign the main port which is the receive port and the
transmitt port, without the 8-bit data for the receive and transmitt
port respectively?

Thanks advance.

Best regards,
Smith

 

[Guenter]

Smith wrote:

Hi all.
I am now trying to test my UART module with using the Spartan 3 board.
As in the UART module, for the submodule of the receiver, I have 8 bit
data to feed the Receive port which is the P3 in the Spartan 3.
[...]

When I want to generate the UCF file, my problem comes. In the list of
I/O pins, there are the receive port (input) and following by bit 0 to
7 input.

Maybe I don't understand that correct, but is it possible that you are
mixing something up?

I don't have the Spartan 3 board, so I rely on your data. So P3 is the
pin that is connected to the RS232 driver. You call it the receive
port, does that mean it is the RXD signal?

I have an older D2 board, very similar to the Spartan 3 and there in
RS232 terms the board is a DTE. That means the RXD signal is an output
and the TXD is an input.

So P3 would be the serial output of the RXD unit. Function of that unit
is to take parallel data, probably 8-bit wide and generate the serial
RXD signal from it.

Now the question is, where do those parallel data in your design come
from? Do you provide them frome external, so do they come over one of
the expansion ports or do you generate them inside of you logic?

If they come over an expansion port from extern, then you need to
specify that in your ucf file, but if they are generated internal, you
don't have to specifiy them in the ucf file. Only the P3 needs to be
specified.

Hope that helps.

Cheers,

Guenter