General State

 

AD485 is a multifunctional active interface converter from RS-232 to RS-485/RS-422.

This product is compatible for RS-232、RS-485 and RS-422 standards. It can convert the single-ended signal of RS-232 into balanced differential signal of RS-485 or RS-422. RS-232 interface is linked to the computer interface via a DB9 (female) interface. RS-485/RS-422 is connected with patch panel via DB9 needle (male) or directly linked with RJ-45 port of the equipment via RJ-45 port. Due to RS-485 supporting two-wire half Duplex, that is, RS-485 has only a pair of difference circuit to send and receive data, therefore users usually work out a suitable communication protocol, and use Serial interface MODEM controlling signal RTS to adjust the direction of sending and receiving data. The internal circuit of AD-485 interface converter can automatically sense the direction of data current and shift the sending/receiving function control. Forming a convenient RS-485 network, therefore, it is not necessary for the software to compile complex and keep-adjusting RTS signal to control the direction of sending/receiving. The function control of RS-485 is transparent, and it’s not necessary to do any adjustment to the software which is based on the old way of linking of previous RS-232. This product has many advantages, such as small volume, long-distance transmission, high speed, stable performance and external power supply. This product adopts RS-232, RS-485/RS-422 interfaces, which saves the trouble of making hardware or software, is broadly applied in attendance-checking machine, IC card charging system, industry automation control system, bus charging system, canteen charging system and highway charging system.

The characteristics of interface: The interface is compatible with RS-232C, RS-485/ RS-422 standards of EIA.TIA.

Electric interface: RS-232 interface is DB9 interface (female). RS-485/RS-422 interface is DB9 interface (male), or RJ-45 interface. DB9 needle (male) interface can adapt to patch panel, and through binding post it is convenient to wire routing.

Transmission media: RS-485 is using a pair of twisted pairs.( Shielding is allowed  and 120 Ohm of each twisted pair’s impedance is recommended.)

R-422 is using a pair of twisted pair. (Shielded twisted pair is allowed and 120 Ohm of each twisted pair’s impedance is recommended.)

Working mode: RS-422 asynchronous full duplex. RS-485 asynchronous half duplex. Protection rate: 15000V surge protection. Transmission speed: 75~115200bps Transmission distance: 0~1968.5 yards (0~1800 meters) Working condition: 32°~140°F （0℃~60℃） relative humidity 5％~95％ Allowed Amount of Concatenated: 32~128 equipments