适配继电器空的情况

pkg/relay/relay.go

@@ -2,6 +2,7 @@ package relay
 
 import (
 	"github.com/grid-x/modbus"
+	"go.uber.org/zap"
 	"io"
 )
 
@@ -53,6 +54,8 @@ func (r *device) Off(num int) error {
 }
 
 func New(address string) (Relay, error) {
+	zap.S().Infoln("连接继电器: ", address)
+
 	h := modbus.NewRTUClientHandler(address)
 	h.SlaveID = 1
 	h.BaudRate = 9600