Electronic payment terminal with an improved display

1. An electronic payment unit comprising:

a display having first and second terminals for receiving display data;

a first processor connected to the first terminal by a parallel link and adapted to provide display data to the first terminal at a first rate; and

a second processor connected to the second terminal by a serial link and adapted to provide display data to the second terminal at a second rate lower than the first rate and adapted to provide the display with a signal of selection of the display data received on one of the first or second terminals, the second processor being further connected to the first processor and being adapted to provide the first processor with a signal for allowing or forbidding the transmission of display data to the display,

wherein the second processor is adapted to transmit a signal to the first processor allowing the first processor to provide display data to the display when the second processor provides the display with a signal instructing the display to display the display data received on the first terminal, and wherein the second processor provides the first processor with a signal notifying the first processor not to transmit display data to the display when the second processor transmits to the display a signal instructing the display to display the display data received on the second terminal.

2. The unit of claim 1 , wherein the display comprises a third terminal and wherein the second processor is connected to the third terminal and is adapted to provide the selection signal to the third terminal.

3. The unit of claim 1 , wherein the display is a liquid crystal display.

4. The unit of claim 1 , wherein the second processor is connected to a chip card and/or magnetic card reader.

5. The unit of claim 1 , wherein the second processor is connected to a device for detecting an unauthorized access to the unit.

6. A method for displaying display data on a display of an electronic payment unit, said display comprising first and second terminals for receiving display data, the payment unit further comprising a first processor connected to the first terminal by a parallel link and adapted to provide display data to the first terminal at a first rate and a second processor connected to the second terminal by a serial link and adapted to provide display data to the second terminal at a second rate lower than the first rate, the method comprising having the second processor provide the display with a signal for selecting display data received on one of the first or second terminals and providing the first processor with a signal for allowing or forbidding the transmission of display data to the display,

wherein when the second processor provides the display with a signal instructing the display to display the display data received on the first terminal, the second processor transmits a signal to the first processor allowing the first processor to provide display data to the display and wherein, when the second processor transmits to the display a signal instructing the display to display the display data received on the second terminal, the second processor provides the first processor with a signal notifying the first processor not to transmit display data to the display.

7. The method of claim 6 , wherein the display comprises a control unit and a display panel, the control unit adapted to display on the display panel images obtained based on the display data and wherein, before the second processor provide the display with the signal for selecting the display data received on the first terminal, the second processor provides configuration data to the display, the control unit adapted to display images obtained based on the display data received on the first terminal on a portion only of the display panel which depends on the configuration data.