User M anual 1. General The MMI Remote Control (MMI...Multi Media Interface) enables the infotainment systems in Audi vehicles to be remote controlled. The arrangement of the keys and the functionality of the remote control are reproductions of the built-in MMI control panels in the front centre console. It is fitted in a storage dish in the rear of the centre armrest and is foreseen for operation by the passengers in the rear of the car. The controls are a reproduction of the built-
in MMI controls in the front centre console. This means that it is also possible to control everything that can be controlled with the built-in controls using the remote control alone. 2. Structure and Function The remote control is housed in a c. 150mm x 50mm x 30mm individually manufactured plastic casing. The power supply is provided using a 3V Lithium battery (Type CR2). All keys are connected to the controller using a keyboard matrix. Each column in this matrix is also connected to an interrupt input. The switches of the two encoders for the rotary switch are also connected to one interrupt input each. The C is mainly in sleep mode. When a key is touched the C is woken up and starts the key request. After the control that has been touched has been recognised, the HF transmitter is switched on and after a short delay of 10ms the code foreseen for this purpose is added to the one on the modulation input of the HF transmitter. The lighting of the controls is activated at the same time using 8 LEDs. The transmitter is a PLL-IC with a reference frequency of 13.5444 MHz. When the control in question has ceased to be operated the HF transmission ends with the telegram "KeyReleased, and the lighting stays on for another 3seconds. The lighting then switches off and the C goes back into sleep mode. 3. Technical Parameters Transmission frequency [fh - ((fh fL ) / 2)]
Tolerance of the total transmission frequency
(incl. temperature-related deviations) Transmission power @ 25C typ. Modulation Deviation [fh fL] @25C Coding Telegram length Baud rate Working voltage Total current consumption Current consumption for lighting (part of the above) Working temperature range Storage temperature range Europe / USA 433.42MHz 100ppm
<10900V/m@3m
(ca-17dBm) 2FSK 34kHz3kHz Manchester Code 12 Byte 4,500Bit/s 1.5%
2.0V 3,5V
<25mA Approx. 16mA
-40C... +70C
-40C... +90C