how to entrance & fanout internal logic cell

[Altera_Forum]

Hi everybody. 

I use quartusII 9.1-sp1 and i develop on cyclonne-III board with serial flash memory epcs4 with 16mhz crystal. But on my development board, when i add some signals-probes for debugging, or other signals, misteriouly :confused: the board not run correctly :confused:  My dev board is buggy randomly after modify shematic and reprogramming memory of FPGA. Modif is very simple i add/sub not-cell and probes.  I try lcell, but it fell like.  What can i do ?  Please, what is entrance and fanout of general logics-cells Into cycIII fpga or Altera cpld ?  Excuse my bad English.  Thank you.

[Altera_Forum]

--- Quote Start ---  Hi everybody. I use quartusII 9.1-sp1 and i develop on cyclonne-III board with serial flash memory epcs4 with 16mhz crystal. But on my development board, when i add some signals-probes for debugging, or other signals, misteriouly :confused: the board not run correctly :confused:  My dev board is buggy randomly after modify shematic and reprogramming memory of FPGA. Modif is very simple i add/sub not-cell and probes.  I try lcell, but it fell like.  What can i do ?  Please, what is entrance and fanout of general logics-cells Into cycIII fpga or Altera cpld ?  Excuse my bad English.  Thank you.  --- Quote End ---    Hi,  I assume you add some connection to signal, which you would like to see on FPGA pins. Right ?  Kind regards  GPK

[Altera_Forum]

Thank you for your reply. 

Is the unused pins can cause problems?  Other question : If i make a symbol an i name some signals, for example "clk1" , is that this signal is seen as a global signal, ie that the other symbols take "clk1" into account ?

[Altera_Forum]

--- Quote Start ---  Thank you for your reply.  Is the unused pins can cause problems?  --- Quote End ---    Hi,  first of all you should look to the default setting of unused pins. You can found the setting looking under: Assignment -> Device -> Device and Pin options -> Unused pins Maybe your setting is " Output driven ground". This must be change to "Tri-stated input". When you add a new output did you assign the output to a certain pin ?  Kind regards  GPK

[Altera_Forum]

Hi 

If i understand your reply : into the project settings > device and pin option > unused pin are setting to "as input tri stated with pull up resistor" Thank.

[Altera_Forum]

--- Quote Start ---  Hi If i understand your reply : into the project settings > device and pin option > unused pin are setting to "as input tri stated with pull up resistor" Thank.  --- Quote End ---    Hi,  yes, that should be the first step.  Kind regards  GPK