RS-232 COMMUNICATION PROTOCOL
VS
RS-485 COMMUNICATION PROTOCOL
RS-232 Communication Protocol:
RS232 Communication Protocol is mostly used for connecting two devices one is Data Terminal Equipment (DTE) and the other is Data Communication Equipment (DCE). Their interfaces are most popular in the peripheral connecting for PCs.
The links used in RS232 are classified as unbalanced and single-ended lines, this means the transferring lines are referred to as common ground. One wire is used for transmitting data they carry, and the ground serves as a second wire. Single-ended lines can quickly corrupt the data when they can carry for very long distances.
In terms of electrical characteristics of transmitted signals, the logic level 0 is known as or equal to or more positive than +3V. Logic level 1 is defined as equal to or more negative than -3V. Here the signals use negative logic. There are undefined input signals between -3 and +3 which were stated by the protocols. It is a point-to-point asynchronous communication protocol, which means no common clock is used for synchronizing the transmitter and receiver and they run on their own clock.
RS-485 COMMUNICATION PROTOCOL;
RS-485 Carries the official name TIA/EIA-485. It was designed to increase the distance and data limits of RS_232 and to overcome the one-way communication over a two-wire interface of RS-422. It is a bi-directional multi-drop interface, so it is not limited by connecting only two wires like RS-232.
we can connect up to 32 sets of drivers and receivers in the RS-485 port and the distance extends up to 4000 feet, data rates can transfer up to 100kbps. RS-485 has higher noise immunity. Their line balances out and their voltages cancel each other when there is no data transferred. They are picked up and amplified by the receiver if there is data on their lines.
DIFFERENCE BETWEEN RS-232 AND RS-485:
RS232 Communication Protocol | RS-485 Communication Protocol |
It is used for shorter distances and a lesser data rate | It is used for longer distances with a higher data rate |
It has a maximum cable length of 50 feet and a maximum data rate of 20 Kbps | It has a maximum cable length of 4000 feet and a maximum data rate of 100 Kbps |
It lowers the noise immunity | It offers higher noise immunity |
It uses single-ended lines or unbalanced signaling | It uses balanced differential signaling techniques |
RS-232 is used for connecting only two devices. | RS-485 is designed for multi-point systems |
CONCLUSION:
We conclude that the RS-485 is more advanced and versatile than the RS-232. But for example, if you need to connect the monitor to the CPU RS-232 is good enough for that, so in some cases, RS-232 is more than enough. At last, we can select depending on the type of functions which they required.