Simulation LPM_ADD_SUB - Simulation LPM_ADD_SUB Good morning, 'm trying to simulate a simple three-bit adder with 1 but as soon as I launch ModelSIM and force the input signal to 000 for example, the output signal remains in z state. I also tried to input a clock signal but the output signal always remains in z state. How can I solve this? I expected that, whether forcing the input variable to a value or not, the output variable should increment its value by 1. Attached the drawing I am using. Any Help? Replies: Re: Simulation LPM_ADD_SUB Did you parameterize and generate this? https://www.intel.com/content/www/us/en/docs/programmable/683490/24-1/parameters-22365.html Replies: Re: Simulation LPM_ADD_SUB sorry, the right figure is this