Bhushan: in each constituency the order of symbols... ... Plea For 100% VVPAT Verification Of EVM Votes : Live Updates From Supreme Court

Bhushan: in each constituency the order of symbols will be different and the VVPAT has to print the slip with the symbol, a program has to be installed in each machine to tell it that if number 3 button is pressed then show the symbol in the slip.

So they are programmable chips