Tag Archives: memory

The LG BL20 Chocolate offers impressive slider phone technology

The LG BL20 Chocolate offers impressive slider phone technology

The LG BL20 Chocolate is one of the new arrivals within the LG range of mobile phones. Released in October 2009 this handset has a futuristic design which appeals. Although aesthetically pleasing to the eye, this handset also packs a punch when it comes to functionality. Measuring 106 mm x 50 mm and 12 mm thick this handset is a slim line handset which offers seamless and endearing technology.

This handset comes with a 5 mega pixel camera which operates at a resolution of 2560 x 1920 pixels. The utilisation of Schneider-Kreuznach optics is testimony to LGs emphasis on ensuring quality of image within its camera equipment. In addition the camera provides auto focus and an LED flash for illumination purposes. As an alternative to static imagery the camera also provides the ability to record video at QVGA quality and at 15 frames per second.

The LG BL20 Chocolate comes with a 2.4 inch TFT display screen which is able to display up to 262,000 colours at a pixel size of 240 x 320 pixels. Imagery displayed on the screen is colourful and vivid. The handsets futuristic feel is encompassed within the touch sensitive hidden navigation keys which are on the front panel of the handset and are used for its multitude of functionality. The handset comes with vibration and ring alert types included within the package, however for further individuality the ability to download polyphonic and MP3 ringtones is included. As a means of hands-free communication the phone provides a speakerphone.

Internal memory within this handset is 60 MB, however this can be significantly improved upon by utilising the microSD slot which allows expansion of the memory storage up to a more creditable 16 GB. The handset comes with a variety of additional options which include an MP3/MP4 player, organiser, voice memo and FM radio.

GPRS and EDGE connections are provided within this handset and are both class 12. In addition the handset also provides Blue tooth and USB. This ensures the handset can be connected to multiple devices and seamlessly transfer files or synchronise with a PC as well as providing the means to download the files as and when required.

The LG BL20 is a relatively new entrant into the phone market, yet has already turned heads. It offers unrivalled styling and technology which surpasses many handsets that are available on the current market. The handsets ability to seamlessly perform numerous tasks in a user-friendly manner is one of its key benefits and one that has endeared it to the general public.

For further information on a comprehensive range of mobile phones visit www.phoneslimited.co.uk


CPU Registers and Their Functions

CPU Registers and Their Functions

Registers are the most important components of CPU. Each register performs a specific function. A brief description of most important CPU’s registers and their functions are given below:

1. Memory Address Register (MAR):

This register holds the address of memory where CPU wants to read or write data. When CPU wants to store some data in the memory or reads the data from the memory, it places the address of the required memory location in the MAR.

2. Memory Buffer Register (MBR):

This register holds the contents of data or instruction read from, or written in memory. The contents of instruction placed in this register are transferred to the Instruction Register, while the contents of data are transferred to the accumulator or I/O register.

In other words you can say that this register is used to store data/instruction coming from the memory or going to the memory.

3. I/O Address Register (I/O AR):

I/O Address register is used to specify the address of a particular I/O device.

4. I/O Buffer Register (I/O I3R):

I/O Buffer Register is used for exchanging data between the I/O module and the processor.

5. Program Counter (PC)

Program Counter register is also known as Instruction Pointer Register. This register is used to store the address of the next instruction to be fetched for execution. When the instruction is fetched, the value of IP is incremented. Thus this register always points or holds the address of next instruction to be fetched.

6. Instruction Register (IR):

Once an instruction is fetched from main memory, it is stored in the Instruction Register. The control unit takes instruction from this register, decodes and executes it by sending signals to the appropriate component of computer to carry out the task.

7. Accumulator Register:

The accumulator register is located inside the ALU, It is used during arithmetic & logical operations of ALU. The control unit stores data values fetched from main memory in the accumulator for arithmetic or logical operation. This register holds the initial data to be operated upon, the intermediate results, and the final result of operation. The final result is transferred to main memory through MBR.

8. Stack Control Register:

A stack represents a set of memory blocks; the data is stored in and retrieved from these blocks in an order, i.e. First In and Last Out (FILO). The Stack Control Register is used to manage the stacks in memory. The size of this register is 2 or 4 bytes.

9. Flag Register:

The Flag register is used to indicate occurrence of a certain condition during an operation of the CPU. It is a special purpose register with size one byte or two bytes. Each bit of the flag register constitutes a flag (or alarm), such that the bit value indicates if a specified condition was encountered while executing an instruction.

For example, if zero value is put into an arithmetic register (accumulator) as a result of an arithmetic operation or a comparison, then the zero flag will be raised by the CPU. Thus, the subsequent instruction can check this flag and when a zero flag is “ON” it can take, an appropriate route in the algorithm.