According to the manual for the 32SII (and this is pretty much verbatim from the manual), Flag 11 controls prompting when executing equations in a program, but does not affect automatic prompting during keyboard execution.
When Flag 11 is clear (default), evaluation, SOLVE, and integration of equations proceed without interruption. The current value of each variable in the equation is automatically recalled each time the variable is encountered. INPUT prompting is not affected.
When Flag 11 is set, each variable is prompted for when it is first encountered in the equation. A prompt for a variable occurs only once, regardless of the number of times the variable appears in the equation. When solving, no prompt occurs for the unknown; when integrating, no prompt occurs for the the variable of integration. Prompts halt execution. Pressing R/S resumes the calculation using the value for the variable you keyed in, , or the displayed (current) value of the variable if R/S is your sole response to the prompt.
Flag 11 is automatically cleared after evaluation, SOLVE, or integration of an equation in a program. The status of Flag 11 is also controlled by execution of the SF and CF operations from the keyboard, or by SF and CF statements in programs.
Don't you love the "Old HP's" clear and complete documentation ......