General Description: In Foundation Schematic, I am working on a large schematic with many symbols. I add a component, save, and exit; when I reload the schematic, it appears that the components are missing, and the following message is reported in the Project Manager window:
"Symbol not added. Not enough memory to complete this operation."
Foundation Schematic limits the number of symbols or components that can be added to a particular sheet. You may create a new sheet on the same level, or you can create a hierarchical symbol out of a section of that particular sheet, if applicable. The components may be placed on the new sheet, and the signals that are common between the two sheets will be connected as long as they are labeled in exactly the same way.
To create a new sheet, go to File -> New Sheet; a new sheet with the name of the project (that includes an incremented number appended to the end of the name from the previous sheet) will be added to the current project when the sheet is saved (e.g., the first sheet would be "project_name1.sch", and the new sheet would be "project_name2.sch"). You may also use File -> Save As to name this new sheet, and this name will be added to the current project.
To connect signals between the sheets, label the nets in exactly the same way. As long as the sheets are on the same level, the nets will be connected. You can create open-ended signals that extend from one sheet to the next in the following manner:
- Begin the net from the symbol by using a left-mouse click, then drawing the net. End it in free space by right-clicking your mouse. - Immediately click on the "Add Net or Bus Name" icon, and give the appropriate name. (This icon is on the left-side icon bar and has a net tap with a red "A" on it.)
This procedure may also be used on the other sheet.
To create a hierarchical symbol, you can use File -> New sheet, and create the new schematic. The logic may then either be added to the sheet, or cut and pasted from the previous sheet.
On a hierarchical symbol, the signals that connect to pins on the symbol must have green "I/O Terminals" placed on them. To place an I/O Terminal:
- Select the "I/O Terminal" icon from the left-side icon bar or from the "SC Symbols Library" icon. - Then, select Hierarchy -> Create Macro from the current sheet, and enter the symbol name in the appropriate place. (The inputs and outputs will already be defined). - Press "OK". The new symbol can now be selected from the SC symbols library listing and placed on any sheet.