Specifications:
Working Voltage: 5V
Main Chip: MAX485
Speeds: up to 2.5Mbit/Sec
Distances: up to 1200 meters
Multi-drop supports: up to 32 devices on the same bus
Uses differential signaling for noise immunity
On board 5.08(mm) 2P connector for RS 485 wires

All the pins of the chip are brought out, and can be controlled by MCUPIN:
VCC: 5V
A: Non-inverting receiver input and non-inverting driver output
B: Inverting receiver input and inverting driver output
GND: 0V
R0: Receiver output (to RX pin of microcontroller)
RE: Receiver output enable (low to enable)
DE: Driver output enable (high to enable)
DI: Driver input (to Tx pin of microcontroller)

Package includes:
12 x MAX485 TTL to RS-485 interface module