So here is a “home-made mainframe”, Arduino UNO running a sort of little virtual machine / programming environment, controlled by punchcards, and running a program to add two numbers, displaying thereafter the result: [https://www.youtube.com/watch?v=yizQKRKVQDU](https://www.youtube.com/watch?v=yizQKRKVQDU) \- this is the second of four Arduino punchcard adventures… The code is here: [https://github.com/KedalionDaimon/arduino-punchcard-readers/blob/main/1V0\_20221214\_TZIII\_PUNCHCARD\_UNO.ino](https://github.com/KedalionDaimon/arduino-punchcard-readers/blob/main/1V0_20221214_TZIII_PUNCHCARD_UNO.ino) \- but a full description of the 1V0 Tz III programming language / environment will come at a later point in time.