I am trying to model an ATM system in uppaal and I want to use a json array like a database for card_IDs and pin numbers like this : [ { id : 12548, pin: 1244 }] is this possible or not?
No, JSON syntax is not supported. But it is possible to initialize in bulk, e.g.:
typedef struct { int id, pin; } id_pin_t;
id_pin_t array[3] = {{1,2}, {3,4},{5,6}};