That sounds a bit like the patch cards for the EMS VCS3; you puhed pins into the square patchboard to connect-up the modules. If you mounted a piece of card over the patchboard and pushed the pins through that, the card became a record of your patch.
Of course, you couldn't "read" the card and guess what it souned like; the patchcard didn't record the settings of the knobs either.
Of course, you couldn't "read" the card and guess what it souned like; the patchcard didn't record the settings of the knobs either.