All Mobiles Secret Codes

Samsung Secret Codes

Software Version: *#9999#

IMEI number: *#06#

Serial number: *#0001#

Battery status- Memory capacity : *#9998*246#

Debug screen: *#9998*324# - *#8999*324#
LCD kontrast: *#9998*523#

RELAYS

A relay is usually an electromechanical device that is actuated by an electrical current. The current flowing in one circuit causes the opening or closing of another circuit.

Relays are the devices that detect conditions in circuits and cause the contacts to be ON or OFF to CLOSE or OPEN the circuit as required with suitable arrangements.

HOW RELAY WORKS?

Improving the stability of a crystal oscillator

• If you want a general crystal-controlled embedded system to
keep accurate time, you can choose to keep the device in an
oven (or fridge) at a fixed temperature, and fine-tune the

software to keep accurate time. This is, however, rarely
practical.

• ‘Temperature Compensated Crystal Oscillators’ (TCXOs)
are available that provide - in an easy-to-use package - a
crystal oscillator, and circuitry that compensates for changes
in temperature. Such devices provide stability levels of up to
±0.1 ppm (or more): in a clock circuit, this should gain or
lose no more than around 1 minute every 20 years.
TCXOs can cost in excess of $100.00 per unit...

• One practical alternative is to determine the temperature frequency
characteristics for your chosen crystal, and include
this information in your application.
For the cost of a small temperature sensor (around $2.00),
you can keep track of the temperature and adjust the timing
as required.

Reading and writing individual port pins.

/*-------------------------------------------------------------*-
Reading and writing individual port pins.
NOTE: Both pins on the same port
-*-------------------------------------------------------------*/
#include <reg52.H>
void Write_Bit_P1(const unsigned char, const bit);

bit Read_Bit_P1(const unsigned char);
/* ............................................................... */
void main (void)
{
bit x;
while(1)
{
x = Read_Bit_P1(0); /* Read Port 1, Pin 0 */
Write_Bit_P1(1,x); /* Write to Port 1, Pin 1 */
}
}
/* --------------------------------------------------------------- */
void Write_Bit_P1(const unsigned char PIN, const bit VALUE)
{
unsigned char p = 0x01; /* 00000001 */
/* Left shift appropriate number of places */
p <<= PIN;
/* If we want 1 output at this pin */
if (VALUE == 1)
{
P1 |= p; /* Bitwise OR */
return;
}
/* If we want 0 output at this pin */
p = ~p; /* Complement */
P1 &= p; /* Bitwise AND */
}

Bluetooth

 Bluetooth is a specification (IEEE 802.15.1) for the use of low-power radio communications to link phones, computers and other network devices over short distances without wires. The name Bluetooth is borrowed from Harald Bluetooth, a king in Denmark more than 1,000 years ago.

Bluetooth technology was designed primarily to support simple wireless networking of personal consumer devices and peripherals, including cell phones, PDAs, and wireless headsets. Wireless signals transmitted with Bluetooth cover short distances, typically up to 30 feet (10 meters). Bluetooth devices generally communicate at less than 1 Mbps.

Bluetooth networks feature a dynamic topology called a piconet or PAN. Piconets contain a minimum of two and a maximum of eight Bluetooth peer devices. Devices communicate using protocols that are part of the Bluetooth Specification. Definitions for multiple versions of the Bluetooth specification exist including versions 1.1, 1.2 and 2.0.

Although the Bluetooth standard utilizes the same 2.4 Ghz range as 802.11b and 802.11g, Bluetooth technology is not a suitable Wi-Fi replacement. Compared to Wi-Fi, Bluetooth networking is much slower, a bit more limited in range, and supports many fewer devices.

Concerns with Bluetooth technology include security and interoperability with other networking