#Rs232 serial communication basics driver#

Here is a list of signals used in RS232 pinout. Some of them are common ground, Data, control and timing signals. DB9 connector has 9 pins and DB25 connector has 25 pins with each pin having its own function.ДЄpart from the electrical characteristics, RS232 defined the functions of signals that are used in the serial interface. The D-sub connectors (DB9, DB25) comes with male and female cable. RS232 determines the communication between the DTE and DCE using DB9 and DB25 connectors. Note: The baud rate has to be same at both the transmitter side and receiver side. It determines the speed at which data is to be sent from the transmitter to the receiver. RS232 supports baud rates from 110 to 230400. It is the number of binary bits transferred per second. The advantage of the single-ended technique is, it requires fewer wires to transmit information.

#Rs232 serial communication basics driver#

Single-ended signals are affected by the noise induced by differences in ground voltages of the driver and receiver circuits. This means one wire transmits an altering voltage and another wire is connected to ground.

The RS232 devices work on single-ended signaling (two wire). The impedance bridging between RS232 driver and the receiver is defined to maximize the voltage transfer between the transmitter and receiver. Normally, the maximum slew rate allowed is 30V/Вµsec.

The RS232 standard maintains a minimum slew rate with slow rise and fall time to reduce the cross-talk between neighbouring signals. The change of input voltage determines the rate at which the RS232 driver responds. The voltage from -3V to +3V is considered as an indeterminate state. Whereas the control voltage signals use negative logic, i.e., logic вЂ1вЂ™ indicates -3 to -25 volts and logic вЂ0вЂ™ indicates +3V to +25V. The signal voltage between +3V to +25V represents logic вЂ1вЂ™ and the signal voltages between -3V to -25V represents logic вЂ0вЂ™.