Merge pull request #3 from electricimp/develop

1.0.0

Author: Pavel Petroshenko

.gitignore

@@ -0,0 +1,6 @@
+*.swp
+*.out.*
+.DS_Store
+.build_api_key.json*
+.imptest*
+settings.wrench*

DHCP/README.md

@@ -0,0 +1,127 @@
+# Wiznet 5500 DHCP
+
+This library class enables Dynamic Host Configuration Protocol (*DHCP*) functionality for the Wiznet W5500 chip [W5500](http://wizwiki.net/wiki/lib/exe/fetch.php?media=products:w5500:w5500_ds_v106e_141230.pdf). It also requires the Wiznet W5500 driver.  
+**To add this code to your project, add `#require W5500.DHCP.device.nut:1.0.0` after `#require W5500.device.nut:1.0.0` to the top of your device code.**
+
+## Class W5500.DHCP
+
+### Constructor: W5500.DHCP(*wiz*)
+Instantiates a new W5500.DHCP object and passes in the wiznet main driver.
+
+#### Example Code:
+```squirrel
+// Setup for an Imp 005
+// Initialise SPI port
+interruptPin <- hardware.pinXC;
+resetPin     <- hardware.pinXA;
+spiSpeed     <- 1000;
+spi          <- hardware.spi0;
+spi.configure(CLOCK_IDLE_LOW | MSB_FIRST | USE_CS_L, spiSpeed);
+
+// Initialise Wiznet and DHCP
+wiz  <- W5500(interruptPin, spi, null, resetPin);
+dhcp <- W5500.DHCP(wiz);
+```
+
+## Class Methods
+
+### onLease(*callback*)
+The *onLease()* method sets the function to be called when an IP address is leased. It can be used before or after `dhcp.init()` is called. The callback function has an error parameter which informs the user of timeouts and errors.
+
+#### Parameters
+| Key                  | Data Type   | Required | Default Value | Description                                                    |
+| -------------------- | ----------- | -------- | ------------- | -------------------------------------------------------------- |
+| *callback* | `function`| Yes| N/A| The function to be fired when a DHCP lease is established   |
+
+#### Callback Parameters
+| Key        | Data Type   |Description                                       |
+| -----------| ----------- |------------------------------------------------- |
+| *error*    | `string`    | A string error message                           |
+
+#### Error Messages
+|Error Message                  | Description                                 |
+|-------------------------------|---------------------------------------------|
+|Offer Timeout             		|Discovery message sent with no response      |
+|Ack Timeout               		|Request message sent with no response        |
+|Renewal Timeout           		|Max Renewal attempts reached. Restart.       |
+|Renewal Failed                 |Lease renewal failed                         |
+|Request Declined               |Requested IP not able to be leased           |
+|IP in use                      |Offered IP is currently in use               |
+|All connections in use         |All Wiznet sockets are in use                |
+
+
+
+#### Example Code:
+```squirrel
+dhcp.onLease(function(error) {
+    if (error) return server.error(error);
+});
+dhcp.renewLease();
+```
+
+### renewLease()
+The *renewLease()* method renews the lease or requests a new lease. When this is complete the onLease() callback will be called
+
+#### Example Code:
+```squirrel
+dhcp.onLease(function(error) {
+    // Run this code when IP address is obtained
+});
+dhcp.renewLease();
+```
+
+
+### getIP()
+The *getIP()* method returns the leased IP as an array of four integers. 
+
+#### Example Code:
+```squirrel
+local ip = dhcp.getIP();
+server.log(format("ip = %d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]))
+```
+
+
+### getSubnetMask()
+The *getSubnetMask()* method returns the DNS as an array of four integers. 
+
+#### Example Code:
+```squirrel
+local subnet_mask = dhcp.getSubnetMask();
+server.log(format("subnet mask = %d.%d.%d.%d", subnet_mask[0], subnet_mask[1], subnet_mask[2], subnet_mask[3]))
+```
+
+
+### getRouterAddress()
+The *getRouterAddress()* method returns the gateway address as an array of four integers. 
+
+#### Example Code:
+```squirrel
+local router = dhcp.getRouterAddress();
+server.log(format("router = %d.%d.%d.%d", router[0], router[1], router[2], router[3]))
+```
+
+
+### getLeaseTime()
+The *getLeaseTime()* method returns the lease duration as an integer. 
+
+#### Example Code:
+```squirrel
+local leasetime = dhcp.getLeaseTime();
+```
+
+
+### getDNS()
+The *getDNS()* method returns the DNS as an array of DNS entries, each an array of four integers. 
+
+#### Example Code:
+```squirrel
+local dns = dhcp.getDNS();
+```
+
+
+
+## Extended Example on IMP0005
+View [example.device.nut](example.device.nut) for an extended example.
+
+## License
+The Wiznet code is licensed under the [MIT License](./LICENSE).