Serial communication with 8051

i want detail serial communication help so help me

"8051 Tutorial: Serial Communication"
**broken link removed**

Regards,
IanP

hai
serialcommunication uses the old rs 232 protocol
where we have to set the number of data bits,parity,baud rate
when a microcontroller communicates with other,all these parameters of both the controllers should be the same for propper communication
the tx of first controller should be connected to the rx of the second and the tx of the second to the rx of the first
the ground of both also should be connected.that means we need three wires required.you can send the data upto 10 meters .
whatever you arites to the sbuf of one microcontroller will reaches the sbuf of the second one.when the entire data is transmitted, the ti flag of first controller will set and it will interrupt the system.the same way when all the data bits are received, the ri flag of the second controller will set and will interrupt the controller.the vector address for serila communication is 0023.only one vector for serial communication.you have to write a software to check whether you received or transmitted by checking the ti and ri flags

regards

sun

Devices which use serial cables for their communication are split into two categories. These are
DCE (Data Communications Equipment) and DTE (Data Terminal Equipment.) Data Communications
Equipment are devices such as your modem, TA adapter, plotter etc while Data Terminal Equipment is
your Computer or Terminal.
The electrical specifications of the serial port is contained in the EIA (Electronics Industry
Association) RS232C standard. It states many parameters such as -
1. A "Space" (logic 0) will be between +3 and +25 Volts.
2. A "Mark" (Logic 1) will be between -3 and -25 Volts.
3. The region between +3 and -3 volts is undefined.
4. An open circuit voltage should never exceed 25 volts. (In Reference to
GND)
5. A short circuit current should not exceed 500mA. The driver should be
able to handle this without damage. (Take note of this one!)

Serial Ports come in two "sizes", There are the D-Type 25 pin connector and the D-Type 9 pin connector both of which are male on the back of the PC, thus you will require a female connector on
your device.

In 8051 the serial communication is based on RS - 232. It includes following:
1. The protocol to be used for data transmission.
2. The voltages to be used on the signal lines.
3. The connectors to be used to link equipment together.
Overall, the standard is comprehensive and widely used, at data transfer rates of
up to around 115 or 330 kbits / second (115 / 330 k baud). Data transfer can be
over distances of 15 metres or more.
Note that RS-232 is a peer-to-peer communication standard. Unlike – for example
– the RS-485 standard, RS-232 is intended to link only two devices together.

RS-232 is a byte-oriented protocol. That is, it is intended to be used to send single
8-bit blocks of data. To transmit a byte of data over an RS-232 link, we generally
encode the information as follows:
 We send a ‘Start’ bit.
 We send the data (8 bits).
 We send a ‘Stop’ bit (or bits).

If anything more you want to know you can google on serial communication or can again write if you have any doubt.