Archive:Cash Register Display
| Cash Register Display Release status: experimental [box doku] | |
|---|---|
| Description | Display text in the space |
| Author(s) | tarwin,tiefpunkt |
We have a VFD Display in a strong metal casing, which used to belong to a fast-food cash register.
Hardware
The display is a 2x20 VFD display, which is controled via a serial interface. Inside used to be an interface board.
Display Board
The display board takes 5V at ~0.6A. There's a 7 pin connector to connect to the interface board.
| Pin | Function |
|---|---|
| 1 | 5V |
| 2 | 5V |
| 3 | Reset |
| 4 | Data (RX) |
| 5 | |
| 6 | GND |
| 7 | GND |
There used to be a 1.3A fuse on the board. That burned, and now needs replacement.
Interface Board
The interface board connected the display board to the outside world. It took some higher voltage to convert it to 5V, and RS-232 levels to TTL level understood by the display board.
It seems that the board does not work anymore. Tests showed that the voltage regulator outputs ~10V instead of 5V.
Electric Imp
Instead of connecting via the supplied RJ45 cable to the serial board, an Electric Imp was used to connect the display to the net. The display's RX is connected the Imp (UART12)
