diff --git a/0.9.2/512k-flash/nodemcu_512k.bin b/0.9.2/512k-flash/nodemcu_512k.bin
index d8371e03..65a70e58 100644
Binary files a/0.9.2/512k-flash/nodemcu_512k.bin and b/0.9.2/512k-flash/nodemcu_512k.bin differ
diff --git a/README.md b/README.md
index 9d15998b..6eddb6e8 100644
--- a/README.md
+++ b/README.md
@@ -1,9 +1,11 @@
 # **NodeMcu** #
 ###A lua based firmware for wifi-soc esp8266
-version 0.9.2 build 2014-12-04
+version 0.9.2 build 2014-12-07
 # Change log
-2014-12-04<br />
-fix memory leak issue when input and run from console.
+2014-12-07<br />
+add ow(1-wire module), from arduino, and use same api.<br />
+add an 18b20 1-wire example.<br />
+change net.socket.send() payload max len from 256 to 1460.
 
 [more change log](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_en#change_log)<br />
 [更多变更日志](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_cn#change_log)
@@ -11,7 +13,7 @@ fix memory leak issue when input and run from console.
 - Easy to access wireless router
 - Based on Lua 5.1.4
 - Event-Drive programming preferred.
-- Build-in file, timer, pwm, i2c, net, gpio, wifi, adc, uart and system api.
+- Build-in file, timer, pwm, i2c, 1-wire, net, gpio, wifi, adc, uart and system api.
 - GPIO pin re-mapped, use the index to access gpio, i2c, pwm.
 - GPIO Map Table:
 
diff --git a/examples/ds18b20.lua b/examples/ds18b20.lua
new file mode 100644
index 00000000..ed29efa4
--- /dev/null
+++ b/examples/ds18b20.lua
@@ -0,0 +1,50 @@
+-- 18b20 Example
+pin = 9
+ow.setup(pin)
+count = 0
+repeat
+  count = count + 1
+  addr = ow.reset_search(pin)
+  addr = ow.search(pin)
+  tmr.wdclr()
+until((addr ~= nil) or (count > 100))
+if (addr == nil) then
+  print("No more addresses.")
+else
+  print(addr:byte(1,8))
+  crc = ow.crc8(string.sub(addr,1,7))
+  if (crc == addr:byte(8)) then
+    if ((addr:byte(1) == 0x10) or (addr:byte(1) == 0x28)) then
+      print("Device is a DS18S20 family device.")
+        repeat
+          ow.reset(pin)
+          ow.select(pin, addr)
+          ow.write(pin, 0x44, 1)
+          tmr.delay(1000000)
+          present = ow.reset(pin)
+          ow.select(pin, addr)
+          ow.write(pin,0xBE,1)
+          print("P="..present)  
+          data = nil
+          data = string.char(ow.read(pin))
+          for i = 1, 8 do
+            data = data .. string.char(ow.read(pin))
+          end
+          print(data:byte(1,9))
+          crc = ow.crc8(string.sub(data,1,8))
+          print("CRC="..crc)
+          if (crc == data:byte(9)) then
+             t = (data:byte(1) + data:byte(2) * 256) * 625
+             t1 = t / 10000
+             t2 = t % 10000
+             print("Temperature="..t1.."."..t2.."Centigrade")
+          end                   
+          tmr.wdclr()
+        until false
+    else
+      print("Device family is not recognized.")
+    end
+  else
+    print("CRC is not valid!")
+  end
+end
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