The Z # (calc-kbd-query) command prompts for an algebraic
entry which takes its input from the keyboard, even during macro
execution. All the normal conventions of algebraic input, including the
use of $ characters, are supported. The prompt message itself is
taken from the top of the stack, and so must be entered (as a string)
before the Z # command. (Recall, as a string it can be entered by
pressing the " key and will appear as a vector when it is put on
the stack. The prompt message is only put on the stack to provide a
prompt for the Z # command; it will not play any role in any
subsequent calculations.) This command allows your keyboard macros to
accept numbers or formulas as interactive input.
As an example, 2 RET "Power: " RET Z # 3 RET ^ will prompt for input with “Power: ” in the minibuffer, then return 2 to the provided power. (The response to the prompt that’s given, 3 in this example, will not be part of the macro.)
See Keyboard Macro Query in the Emacs Manual, for a description of
C-x q (kbd-macro-query), the standard Emacs way to accept
keyboard input during a keyboard macro. In particular, you can use
C-x q to enter a recursive edit, which allows the user to perform
any Calculator operations interactively before pressing C-M-c to
return control to the keyboard macro.