User Guide

Figure 97 SIM interface

Retu handles SIM card detection and the detection method is based on the BSI line. Due to location of the SIM

card removal of the battery causes quick power down of the SIM IF. The Retu SIM1 interface supports both the

1.8V and 3.0V SIM cards. SIM interface voltage is first 1.8V when the SIM card is inserted and if the card does not

response to the ATR (Answer To Reset) 3V interface voltage is used. The data communication between the card

and the phone is asynchronous half duplex and the clock supplied to cards is 1-5MHz, which is 3.2MHz by default

(in GSM system). The data baud rate is SIM card clock frequency divided by 372 (by default), 64, 32 or 16.

RS MMC interface

The reduced size (24mm x 18mm x 1.4mm) multimedia card slot is located under the battery. The device

supports RS MMC hot insertion so it is possible to remove/insert the card when the phone is powered on.

Figure 98 Reduced size MMC

RS MMC card is connected to the Helen3 processor MMC/SDIO2 (1.8V) interface. MMC interface is shown in the

following figure:

RM-1

Nokia Customer Care System Module

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