ConstThe mode and the toggle are workbook commands (calcMode*, calcIterativeToggle in
WorkbookCommands); the limits are not commands — they are number fields written straight to
ICalculation.setIterativeCalculation. Registered as calculationOptions (the Formulas tab) and
mounted again in the formula bar.
Excel's Calculation Options as one popup: the calculation-mode radio (Automatic / Automatic Except for Data Tables / Manual), Enable Iterative Calculation with its Maximum Iterations and Maximum Change, and the two recalculations (Calculate Now, Calculate Full).