Cadence problem with using a design in another project

[husseinadel]

hello

i am working on cadence/spectre, i make a design and i wish to use it in another one ,,so i make it as symbol and add it by "add instance " in the new design,,i use 3 of it ,,the problem iis that it gives me error when connecting two of them together ,,it says " warning pin outp(i named this pin outp while making the symbol) on instance Io floating input " although i connect ithem with each other

any help plz

 

[eng_Semi]

Re: cadence problem

check that u dont short two output ports.

Can u send a snapshot for the schematic ?

 

[husseinadel]

Re: cadence problem

check that u dont short two output ports.

Can u send a snapshot for the schematic ?

many thanks for your replying,,i used pins of specified direction i.e. input and output pins,,this makes the problem above,,,,when i made them inout pins ,,it gives no warnings and the problem solved,,,,,,i dont know why really,,,,,,

 

[Hughes]

cadence problem

If you short two outputs, you will get a warning about shorted outputs. If a input terminal doesn't connect with any output or inout terminal, you will a warning about floating input. Both rule can be changed.

Although you know the terminals you connected toghether doesn't need another driving source, Cadence can only determine it from the direction of pins. If all pins connected together are input pins, all of them will be considered to expect a driving signal, and don't have the capability to driving others. So you will get such a warning.

 

[husseinadel]

Re: cadence problem

If you short two outputs, you will get a warning about shorted outputs. If a input terminal doesn't connect with any output or inout terminal, you will a warning about floating input. Both rule can be changed.

Although you know the terminals you connected toghether doesn't need another driving source, Cadence can only determine it from the direction of pins. If all pins connected together are input pins, all of them will be considered to expect a driving signal, and don't have the capability to driving others. So you will get such a warning.

thanks for replying,,,but when i connect them i connect the output pins with the input ones,,so i expect that it is ok,,but the pb above appears ,,when i change the pins to inout type,,it works,,,

 

[husseinadel]

Re: cadence problem

hello
i have another problem,, while simulating noise using spectre,,,it stopped simulating when it reaches about 39% and return an error "simulation time exceeds the limit" ,,,can anybody interpret this strange error????

 

[Hughes]

Re: cadence problem

thanks for replying,,,but when i connect them i connect the output pins with the input ones,,so i expect that it is ok,,but the pb above appears ,,when i change the pins to inout type,,it works,,,

If you connect the output pin of instance A with input pins of instance B and C, and the problem appears, it is a strange problem. But if you put a output pin "outp" and connect the input pins of B and C together with "oup", you will certainly get the warning.

 

[husseinadel]

Re: cadence problem

thanks for replying,,,but when i connect them i connect the output pins with the input ones,,so i expect that it is ok,,but the pb above appears ,,when i change the pins to inout type,,it works,,,

If you connect the output pin of instance A with input pins of instance B and C, and the problem appears, it is a strange problem. But if you put a output pin "outp" and connect the input pins of B and C together with "oup", you will certainly get the warning.

then it is a strange problem, ijust connect outp to inp