User's Manual
Table Of Contents
- Contents
- Figures
- Tables
- Document history
- Introduction
- Product concept
- GSM application interface
- GSM/GPRS operating modes
- Power supply
- Power up / down scenarios
- Automatic GPRS Multislot Class change
- Charging control of the GSM part
- Power saving
- Summary of state transitions (except SLEEP mode)
- RTC backup for GSM part of XT55/56
- Serial interfaces of the XT55/56 GSM part
- Audio interfaces
- SIM interface
- Control signals
- GPS application interface
- GSM and GPS antenna interfaces
- Electrical, reliability and radio characteristics
- Mechanics
- Reference approval
- Example applications
- List of parts and accessories
XT55/56 Hardware Interface Description
Confidential / Released
s
XT55/56_hd_v02.06a Page 94 of 125 17.12.2004
Function Signal name IO Signal form and level Comments
Digital Input /
Output
GPS_GPIO14 I/O CMOS 3.3V DC level See Chapter 4.5
Digital Input /
Output
GPS_GPIO15 I/O CMOS 3.3V DC level See Chapter 4.5
GPS Reset GPS_M-RST I CMOS 3.3V DC level Active low reset input
Serial1 Rx GPS_SDI1 I CMOS 3.3V DC level See Chapter 4.6
Serial1 Tx GPS_SDO1 O CMOS 3.3V DC level See Chapter 4.6
Digital Input GPS_BOOTSEL I CMOS 3.3V DC level For re-programming the
Flash must be set to High
Digital Input GPS_RFPC1 I CMOS 3.3V DC level
Connect to GPS_GPIO4
including the pull-up
resistors as shown in Figure
58
Digital Input GPS_RFPC0 I CMOS 3.3V DC level
Connect to GPS_GPIO8
including the pull-up
resistors as shown in Figure
58
Serial2 Rx GPS_SDI2 I CMOS 3.3V DC level See Chapter 4.6
Serial2 Tx GPS_SDO2 0 CMOS 3.3V DC level See Chapter 4.6
CMOS 3.3V level:
Input High = 2.0 – 3.3 V DC; I_leakage = 2µA
Input Low = 0 – 0.8 V DC, I_leakage = 2µA
Output High = min. 2.4 V DC, I
oh
= 2mA
Output Low = max 0.4 V DC, I
oh
= 2mA