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SAMSUNG Proprietary-Contents may change without notice
10-3
STH-A225
Circuit Description & Circuit Diagrams
Table1. ARM Memory Map
ARM Memory Map
ARM Address Range
Data
Block Size
Device Name
Remarks
0000 0000
0000 0003
32
4 Byte
Internal ROM
R
0000 0004
0000 1FFF
32
8K Byte
Internal RAM
R/W
0002 0000
0002 0FFF
32
4K Byte
Internal ROM
R
0004 0000
0005 FFFF
32/16
NA
Internal Peripherals
R/W
0080 0000
00FF FFFF
8/16
Up to 8 M Byte
SRAM_CS
R/W
0100 0000
017F FFFF
8/16
Up to 8 M Byte
FLASH_CS
R/W
0180 0000
01FF FFFF
8/16
Up to 8 M Byte
CS_RES1
R/W
0200 0000
027F FFFF
8/16
Up to 8 M Byte
CS_RES2
R/W
HOST CPU (inside of BEC:U203)
ARM7TDMI 32-bit microprocessor is used for the main call processing. The CPU controls all the circuitry. The
reference clock 14.4 MHz, coming from the output of the TCXO (OSC302), is connected to VCTCXO_IN (pin
F3). For the power fail mode and the sleep mode, additional crystal oscillator (U202) of 32.768kHz is connected
to pin B2 of the BEC. The interface circuitry consists of reset circuit, address bus (A0-A21), data bus (AD0-
AD15), control signals (MEMWEB, MEMOEB, SRAM_CS, FLASH_CS, DISPLAY_CS, UBE etc), GPIOs, and the
communication ports. The communication ports includes the UART1 and 2, the JTAG, and the SCI. The UART1
supports HP equipment interface, down loading, and data service. The UART2 and the JTAG are used for the
software debugging. The SCI supports the Diagnostic Monitor (DM) function.
FLASH ROM (inside of U206)
The 32Mbit FLASH ROM is used to store code of the application program. Using the down-loader program,
this application program can be changed even after the mobile is fully assembled.
SRAM (inside of U206)
The 4Mbit SRAM is used to store the internal flag information, call processing data, and timer data.
Key Pad Module
The Key Pad module is connected to main board by connector, CN201-1. For key-press recognition, the
structure of key is consisted of 8 x 3 matrix, which is used GPIO input signal SCAN0-7 and GPIO output signal
KEY0-2 of BEC. In addition, this module contains Micro-phone and six backlight LEDs that will help to operate
phone in the dark.
LCD Module
LCD module is connected to main board by connector, CN101. This contains an LCD controller, an EL (Electro-
Luminescent) driver, a speaker, and a vibrator. An LCD controller controls the information of displaying from
the BEC (parallel 8-bit data) to the LCD. The EL driver IC turns on and off the EL dacklight.
Baseband Engin (inside of U203)
This part mainly interface with IFC (U101) and RF part. As for interface of IFC, that will be explained detail in
next section. As important signals are PREAMP_G for receiver path, PA-GATE, ALC_EN for transmitter path,
PLL_DATA, PLL_CLK, PLL_STRB1 for PLL synthesizer, RX_BAT, TX_BAT for power management.