EmbDev.net

Forum: FPGA, VHDL & Verilog DAC interface on spartan 3E

von Krishna (Guest)

2017-09-12 07:56

Attached files:

DAC.vhd (2.23 KB, 352 downloads) | highlighted code

Rate this post

0	▲ useful ▼ not useful

Here I am trying to make DAC work on boar of FPGA spartan 3E.I write 
code as per manual but it don't give desired output.I attached the code 
here. Can anyone tell me where the problem is?

Report post Edit Move Thread sperren Anmeldepflicht aktivieren Delete topic Thread mit anderem zusammenführen Quote selected text Reply Reply with quote

Re: DAC interface on spartan 3E

von C. A. Rotwang (Guest)

2017-09-12 08:04

Rate this post

0	▲ useful ▼ not useful

Look for a working SPI-Core and use it.

Check the spi protocol with the datasheet of your SPI-DAC. Use 
simulation and compare the waveform of the simulator with that in your 
datasheet

Does your spi-clk toggle? I guess not. And also check the direction of 
the port.

Report post Edit Delete Quote selected text Reply Reply with quote

Re: DAC interface on spartan 3E

von Krishna (Guest)

2017-09-12 09:43

Rate this post

0	▲ useful ▼ not useful

Thank you for your response.
my spi_sck is working proper. And I also check for SPI but I don't find 
any problem with it.I am beginner. if possible,can you explain in detail 
?

Report post Edit Delete Quote selected text Reply Reply with quote

Re: DAC interface on spartan 3E

von C. A. Rotwang (Guest)

2017-09-12 21:45

Rate this post

0	▲ useful ▼ not useful

Krishna wrote:
> Thank you for your response.
> my spi_sck is working proper. And I also check for SPI but I don't find
> any problem with it.I am beginner. if possible,can you explain in detail
> ?

OK, I missed the toggling by "XOR 1'. See it seems to toggle. But i 
assume its not using a IOB-Flipflop. Have you set any constraint? 
Otherwise is likely that the sck takes some ns longer to propagate to 
the pin. Try post place&route simulation or use a scop and check spi set 
and hold times in respect to sck.

https://forums.xilinx.com/t5/Embedded-Development-Tools/Post-Place-and-Route-simulation-with-MicroBlaze/td-p/356313

Report post Edit Delete Quote selected text Reply Reply with quote

Re: DAC interface on spartan 3E

von Krishna (Guest)

2017-09-13 11:16

Rate this post

0	▲ useful ▼ not useful

You are right it is about constrain, I try to solve it but not working. 
it is gives below warnings. can you tell me how to remove that warnings?

WARNING:Xst:1293 - FF/Latch <dacsend_8> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_7> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_6> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_2> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_1> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_0> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_32> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_31> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_30> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_29> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_28> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_27> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_26> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_25> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_24> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_23> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_13> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_12> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_11> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_7> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_6> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_5> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_4> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_3> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_2> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_1> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_0> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_8> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_7> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_6> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_2> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_1> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacsend_0> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_32> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_31> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_30> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_29> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_28> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_27> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_26> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_25> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_24> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_23> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_13> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_12> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_11> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_7> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_6> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_5> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_4> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_3> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_2> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_1> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.
WARNING:Xst:1293 - FF/Latch <dacdata_0> has a constant value of 0 in 
block <DAC>. This FF/Latch will be trimmed during the optimization 
process.

Report post Edit Delete Quote selected text Reply Reply with quote

Re: DAC interface on spartan 3E

von mr_monk (Guest)

2017-09-26 15:54

Rate this post

0	▲ useful ▼ not useful

The warnings are just telling you that your signal "dacsend" is always 
set to all zeros. You never put any other value in there so you have a 
signal stuck at one value.

This is usually not what you want and that is why you are getting a 
warning.

Report post Edit Delete Quote selected text Reply Reply with quote

Watch this topic |

Disable multi-page view

Reply

Entering an e-mail address is optional. If you want to receive reply notifications by e-mail, please log in.

Rules — please read before posting

Post long source code as attachment, not in the text
Posting advertisements is forbidden.

Formatting options

[c]C code[/c]
[avrasm]AVR assembler code[/avrasm]
[vhdl]VHDL code[/vhdl]
[code]code in other languages, ASCII drawings[/code]
[math]formula (LaTeX syntax)[/math]

Contact – Data privacy information – Advertising on EmbDev.net