M
ODEL
SL900A V
ERSION
V_1.0
P
REPARED BY
H/W
D
ATE
2006.06.30
S
UBJECT
T
ECHNICAL
M
ANUAL
P
AGE
19/51
SL900A
T
ECHNICAL
M
ANUAL
In SL900A
, ECS0# is used for External Flash Memory and ECS1# is used for External PSRAM.
4.
Microcontroller Peripherals
Microcontroller(MCU) Peripherals are devices that are under direct control of the Microcontroller. Most of the
devices are attached to the Adcanced Peripheral Bus(APB) of the MCU subsystem, and serve as APB slaves.
Each MCU peripheral must be accessed as a memory-mapped I/O device: that is, the MCU or the DMA bus
master reads from or writes to the specific peripheral by issuing memory-addressed transactions.
4.1
Pulse-Width Modulation Outputs.
Two generic Pulse-Width Modulators are implemented to generate pulse sequences with programmable
frequency and duty cycle for LCD backlight or charging purpose. The duration of the PWM output signal is low
as long as the internal counter value is greater than or equal to the threshold value.
In SL900A
, PWM1 is used for LCD Module Backlight Enable and PWM2 is used for Flash LED Enable.
4.2
SIM Interface
The MT6226M contains a dedicated smart card interface to allow the MCU access to the SIM Card. It can
operate via 5 terminals, using SIMVCC, SIMSEL, SIM RST, SIMCLK and SIMDATA.
The SIMVCC is used to control the external voltage supply to the SIM card and SIMSEL determines the
regulated smart card supply voltage. SIMRST is used as the SIM card reset signal. Besides, SIMDATA and
SIMCLK are used for data exchange purpose. Basically, the SIM interface acts as a half duplex asynchronous
communication port and its data format is composed of ten consecutive bits: a start bit in state Low, eight
information bits and a tenth bit used for parity checking.
In SL900A
, Only 3V SIM interface is used.
Figure 11. SIM interface
4.3
Keypad Scanner
The keypad can be divided into two parts : One is the keypad interface including 7 columns and 6 rows The
other is the key detection block which provides key pressed, key released and de-bounce mechanism. Each time
the key is pressed or released, i.e. something different in the 7x6 matrix, the key detection block will sense it,
and it will start to recognize if it is a key pressed or key released event. Whenever the key status changes and is
stable, a KEYPAD IRQ will be issued. The MCU can then read the key pressed directly in KP_HI_KEY,
KP_MID_KEY and KP_LOW_KEY register.
In SL900A
, The 6 Rows are used (Row0 ~Row5) and The 5 Columns are used (Col 0~3 and Col 6)
Summary of Contents for SL900A
Page 1: ...SL900A SL900A ...
