| 摘要 |
<p>An irrigation controller (200) provides a current to operate an irrigation valve assembly (270) and superimposes a data stream on the current. The current may be either alternating current or direct current. Preferably the current is transmitted over a two-wire link (261, 262). The irrigation valve assembly (272) includes a decoder (271), a solenoid (272) and an irrigation valve (273). The decoder (271) will communicate bi-directionally with the irrigation controller (200). The data stream will be an encoded control signal that is sent at a rate greater than 1 byte per second. The encoded control signal may be sent at a rate greater than or less than the rate of the current.</p> |
