[ePark Systems hack]

I meant that all you need to do is replace the circuit inside with a countdown timer that you can set to whatever you want. what i meant by that it is based on the parking lot enforcer, is that their is no authentication or anything, all they base this on is that the enforcer just sees something that is counting down

Actually there is a series of displays that rotate on the screen. One of the screens says Miami Beach, the next is the parking zone and time limit, next is a security code that is Julian calendar specific and the third is the time of day and finally there is the time and date.

Thus a simple count down timer would not work. However an eprom could be programed to display the above referenced items however the security code screen algorithm would need to be decoded.

[ePark Systems hack]

IMO , you should just gut it and replace the circuitry with your own

It seems like it is all based on the parking lot enforcer

The epark devices in Miami Beach do NOT communicate with anything. They are simply serialized programable (different parking zones) countdown timers. They are "refilled" by providing the serial number. There MUST be a keygen that uses the serial number and the dollar amount requested that generates a resulting "refill" code. All that talk about communicating with some server is meant to mislead you. My guess is each serialized device can only accept a code once. I'm sure the engineers at epark systems thought of these things. I suppose the best way to beat the system would be to clone one device to another and so on. Then just buy the credit once and refill all the devices with the same serial number each time. Or create a keygen somehow.