Khurram Pervaiz BTE-FO5-21

Muhammad Samad Latif BTE-SPO6-056

Aysha Tasneem BTE-SPO6-10

Havaida Batool BTE-SPO6-24

Manchester encoding (first published in 1949) is a synchronous clock encoding technique used by the physical layer to encode the clock and data of a synchronous bit stream. In this technique, the actual binary data to be transmitted over the cable are not sent as a sequence of logic 1's and 0's (known technically as Non Return to Zero (NRZ)). Instead, the bits are translated into a slightly different format that has a number of advantages over using straight binary encoding (i.e. NRZ).

In data transmission, Manchester encoding is a form of digital encoding in which data bits are represented by transitions from one logical state to the other. This is different from the more common method of encoding, in which a bit is represented by either a high state such as +5 volts or a low state such as 0 volts.

ORIn telecommunication, Manchester code (also

known as Phase Encoding, or PE) is a line code in which the encoding of each data bit has at least one transition and occupies the same time. It is, therefore, self-clocking, which means that a clock signal can be recovered from the encoded data.

Manchester code ensures frequent line voltage transitions, directly proportional to the clock rate. This helps clock recovery.

The DC component of the encoded signal is not dependent on the data and therefore carries no information, allowing the signal to be conveyed conveniently by media (e.g. Ethernet) which usually do not convey a DC component.

Before the PIC microcontroller can begin receiving Manchester Encoded data it needs to be properly configured. The microcontroller initialization process comprises setting up the on-board analog comparator circuitry, the two free-running timers, and the two pins as an output and an input.

The analogue comparator circuitry within the PIC microcontroller can be configured to generate an interrupt on any transition that occurs on its input signal line.

This means that a level transition for a logic "0", as well as logic "1" will trigger an interrupt to occur. This allows the microcontroller to decode the Manchester Encoded signal into the proper logic "1" or logic "0" value.

Manchester code is widely-used e in Radio CommunicationsEthernetsBroadband Technologies

Each bit is transmitted in a fixed time (the "period"). A 0 is expressed by a low-to-high transition, a 1 by high-to-low

transition (according to G.E. Thomas' convention -- in the IEEE 802.3 convention, the reverse is true).

The transitions which signify 0 or 1 occur at the midpoint of a period.

Transitions at the start of a period are overhead and don't signify data.

Manchester code always has a transition at the middle of each bit period and may (depending on the information to be transmitted) have a transition at the start of the period also. The direction of the mid-bit transition indicates the data. Transitions at the period boundaries do not carry information. They exist only to place the signal in the correct state to allow the mid-bit transition. Although this allows the signal to be self-clocking, it doubles the bandwidth requirement compared to NRZ coding schemes (or see also NRZI).

In the Thomas convention, the result is that the first half of a bit period matches the information bit and the second half is its complement.

In the next week

1- We will start configuring the free running timers which will assist the Analogue comparator in decoding the data

2- We will start writing the UML (Unified Modeling Language) which will serve as a prelude to our C language cod

THANKS