The maximum cable length depends on the data rate and the type of cable used. As a general rule, the maximum cable length for RS-485 is around 4000 feet (1219 meters) at a data rate of 10 Mbps. However, it's recommended to consult the cable manufacturer's specifications and perform tests to determine the maximum cable length for a specific application.
To ensure reliable communication in a noisy environment, it's recommended to use twisted-pair cables, shielded cables, or cables with built-in noise reduction features. Additionally, implementing error-checking mechanisms, such as CRC or checksum, can help detect and correct errors caused by noise. It's also important to follow proper grounding and termination techniques to minimize noise coupling.
Yes, the SN75182DR can be used in a multi-point configuration, where multiple devices are connected to the same bus. However, it's essential to ensure that only one device is transmitting at a time to avoid data collisions. Implementing a protocol that manages bus access, such as token passing or master-slave architecture, can help prevent data collisions.
The minimum number of devices that can be connected to the bus is two, one transmitter and one receiver. However, the SN75182DR can support up to 32 devices on the bus, depending on the application and the cable length.
To prevent signal reflections, it's recommended to terminate the bus with a 120-ohm resistor at each end of the bus. This ensures that the signal is properly absorbed and does not reflect back into the bus, causing errors or data corruption.
SN75182DR datasheet
by Texas Instruments
