The display unit with 14 individual 7-segment vane displays was purchased from someone selling a whole gas pump but had no information about the control of the display module.

The pcb (made 1985) basically contains the 14 vane displays, a lot of diodes, some pnp und npn transistors and different 74xxx-series logik ics. It seems to be clear, that the whole "intelligence" needed for showing reasonable information while filling the car with fuel is not on the pcb itself but was sitting in some type of controlling-device (probably at the pay desk near the station operator) - unfortunately i neither have such a device, nor the information about the data-interface.

Plan of project milestones:

- Receiving the display unit

- Reverse engineer a schematic

- Understanding the communication interface

- Implementing and testing a microcontroller (probably PIC) based control device

- Decide the way of getting date/time (GPS? DCF77? RTC?) and temperature

- Create a nice and small pcb containing all the functions :-D