WGL Rain8net — Sprinkler Zone Control Protocol Reference

Protocol reference for the WGL/Rain8net irrigation control module — a master/slave RS232-to-network sprinkler zone controller with a hex command protocol for zone control, status requests, and flow/rain sensor input.

Description

A 12-position terminal strip is found on both the slave and master units. Only the master requires a 24VAC source on terminals 11 & 12. Valves on all units (master and slave) connect in the usual manner.

There is a single RS232 (RJ12 jack) connection between the controlling PC and the "master" Rain8. 24VAC power and network communications are passed from master to slave, slave to slave, etc. The network connection for slave units is an 8-conductor RJ45; each unit has a pair of these modular jacks to pass data and power to the next unit in the daisy chain. Each slave unit also has a 6-conductor RJ12 RS232 connection used only to assign the address during initial configuration.

Protocol – Normal Operation

All data in and out is formatted in 3-byte code groups. Configure the serial port as 4800 bps, N-8-1. DTR & RTS should be taken high to provide power for initial configuration.

A free program from Docklight (docklight.de) allows sending and receiving hex commands directly to a Rain8net. Note: the first byte range C0–CF is reserved for MCS use.

Zone ON / OFF Control (Inbound to the Rain8)

• Byte 1 = header (40h)
• Byte 2 = address (01h–FEh)
• Byte 3 = zone number (1–8) in the lower nibble, command (3 = ON, 4 = OFF) in the upper nibble

Example (module address 1): Zone 1 ON = 40 01 31 (hex); Zone 1 OFF = 40 01 41 (hex).

The Rain8 executes the command, then sends back the same three bytes as an ACK.

All Off (Local Module Only)

• Byte 1 = 40h
• Byte 2 = module address
• Byte 3 = 55h

If the address doesn't match any active Rain8 on the network, no response is sent. Otherwise the same three bytes are echoed back and all zones on that module are turned off.

Status Request Response

• Byte 1 = 40h
• Byte 2 = module address
• Byte 3 = F0h

The third byte of the response is the bit pattern of active zones. Example: if zones 1, 2 & 8 are active, the binary response is 10000011 (B3 hex). No response if the address doesn't match any Rain8 on the network.

COM Check

Send 70h in the first byte (remaining two bytes can be anything). Any Rain8 on the line will send back three bytes.

Global All Off

• Byte 1 = 20h
• Byte 2 = 55h
• Byte 3 = 55h

Turns off all zones regardless of address. Does not respond back.

Input Features

Read Rain Switch Status

Send: 50h, module address (hex), EFh. Responds with 50h & EFh in the first two bytes, and 00 (switch closed) or 64h (switch open) in the third byte. No response if no address match or rain sensor option not enabled.

Read Flow Meter Counter

Send: 50h, module address (hex), E0h. Responds with 50h in the first byte and a 16-bit counter value in the last two bytes. No response if no address match or flow meter option not enabled.

Clear Flow Meter Counter

Send: 50h, module address (hex), E7h. Responds by echoing back the command. No response if no address match or flow meter option not enabled.