ComputerCraft Wiki - User contributions [en]

User talk:Rihlsul

2013-03-27T03:05:14Z

Rihlsul: Created page with "Feel free to leave me a note here."

Feel free to leave me a note here.

User:Rihlsul

2013-03-27T03:04:48Z

Rihlsul: created

{{Heading|Background}}
Some stuff about my programming knowledge and other relevant hacky bits.

{{Heading|Programs}}
Coming soon.

{{Heading|Videos}}
Coming soon.

User talk:AfterLifeLochie

2013-03-27T03:04:17Z

Rihlsul: (forgot to sign my note)

Another test. Ignore this.

== Why did you revert my changes on the function and example templates? ==

The 24px ones were really small and blurry. --[[Special:Contributions/67.189.72.22|67.189.72.22]] 13:17, 3 December 2012 (MSK)
* The templates are optimized for screen-readers at present, and are only meant to be a complimentary object. In addition, the files themselves are actually blurry and aren't rendered in high-enough definition. If and when I get FTP access, I can setup a better system than the current one, but the most important point; ''please don't edit live production templates without using a sandbox''. The effects of a template bungle could be a potential eye-sore. ''[[User:AfterLifeLochie|AfterLifeLochie]] 13:22, 3 December 2012 (MSK)''

== APT Minecraft Tekkit window. ==

Lochie, I was viewing your new forum thread on ComputerCraft APT and realised you were running Tekkit. I am glad that not all of the Mod Admins are so hardcoming on the Technic Team. Yours, [[User:Jonjon1234|Jonjon1234]] 15:51, 14 December 2012 (MSK)

== Program Listing? ==

Question for you: As a rookie to CC, I find it really hard to track down APIs or Programs in the forums for such. Sites like Turtlescripts have spawned trying to be a better browseable index of programs.

Would it make sense to have a Program Catalog on the site? I was thinking relatively lightweight, a table with the name, author, summary, current supported version, and a link to the Programs forum thread for it. Possibly have different sections for the major groupings, such as API, OS, Turtles, etc. I can do a mock-up version of what I'm describing if I'm describing poorly. Having posted a couple programs (and more to come), I'd have no issue creating a forum thread, then adding it to a Wiki page. I'd prefer the visibility. [[User:Rihlsul|Rihlsul]] 07:04, 27 March 2013 (MSK)

User talk:AfterLifeLochie

2013-03-27T03:03:46Z

Rihlsul: /* Program Listing? */ new section

Rednet (API)

2013-03-27T02:07:29Z

Rihlsul: Changes to isOpen - description was wrong, was missing link to already created page for it.

{{msgbox
|title=Please Note
|text=As of ComputerCraft 1.5, the Rednet API is just a wrapper for [[Modem_(API)|modems and channels]].
}}

The Rednet API allows computers to communicate between themselves without using redstone wires. In order to send and receive data, a [[modem]] is required. The data is received immediately after sending it, but only by computers within a certain range. That range depends on the altitude of the sending computer increasing with higher altitudes to a max of 384.

<table style="width: 100%; border: solid 1px black; margin: 2px; border-spacing: 0px;">
<tr><td colspan="2" style="font-weight: bold; font-size: large; padding-bottom: .3em; border-bottom: solid #C9C9C9 1px; background: #D3FFC2; line-height:28px;">
[[File:Grid_disk.png|24px]]  
Rednet (API)
</td></tr>

<tr><td style="width: 350px; background: #E0E0E0; padding: .4em; font-weight:bold;">Method Name</td><td style="background: #E0E0E0; padding: .4em; font-weight:bold;">Description</td></tr>

<tr style="background-color: #FFFFFF;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.open]](side)</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Tells the computer that the side can be used for networking.</td></tr>

<tr style="background-color: #E8E8E8;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.close]](side)</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Tells the computer that the side can no longer be used for networking.</td></tr>

<tr style="background-color: #FFFFFF;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.announce]]()</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Broadcasts an empty rednet message.</td></tr>

<tr style="background-color: #E8E8E8;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.send]](receiverID, message)</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Sends a message to the computer using the opened sides. The receiver ID is the ID (number, not string) of the computer you're sending the message to. ID as nil will do the same as a broadcast. The message must be a string to send across rednet, if you are wanting to send a table see [[textutils.serialize]]</td></tr>

<tr style="background-color: #FFFFFF;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.broadcast]](message)</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Sends the message to ALL connected and open computers.</td></tr>

<tr style="background-color: #E8E8E8;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.receive]](timeout)</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Waits until it received a rednet message or <var>timeout</var> has passed. Leave args empty to wait for a message forever.</td></tr>

<tr style="background-color: #FFFFFF;"><td style="border-top: solid #C9C9C9 1px; padding: .4em;">[[rednet.isOpen]](side)</td>
<td style="border-top: solid #C9C9C9 1px; padding: .4em;">Returns true if the wireless modem is open.</td></tr>
</table>

==Events==
{| border="1" cellpadding="2" cellspacing="0"
!style="background:#EEE" width="200px"|Event name
!style="background:#EEE" width="*"|Description
!style="background:#EEE" width="*"|Parameters
|-
|rednet_message
|Fired when a rednet message is received (can be used as alternative for rednet.receive())
|senderId, message, distance
|}

==History==
Before the creation of the in-game wireless networking API, the term "Rednet" referred to a system created by one of the ComputerCraft users based on bundled cables from a popular Minecraft mod - RedPower. It also allowed communication between computers, but the data was transferred slowly - every bit was converted to redstone signal, that lasted about 0,1 seconds. On the release of ComputerCraft 1.3, the system became useless, as the wireless networking was officially implemented to the mod.

[[Category:APIs]]

Modem (API)

2013-03-27T02:02:46Z

Rihlsul: Added to the correct Category

With the advent of ComputerCraft 1.5, the behavior of modems has changed somewhat drastically. Although the rednet api still has the same functionality, it is really just a wrapper for what is a completely different system underneath.

The major change introduced to modems in this version of ComputerCraft is channels: Channels are essentially open networks which can be opened, closed, and listened on by any computer within range. To interact with channels, one must directly wrap the peripheral as opposed to the previous interaction with the rednet API.

Here is a list of functions available from modems:
{| border="1" cellpadding="2" cellspacing="0"
!style="background:#EEE" width="200px"|Function
!style="background:#EEE" width="*"|Description
|-
|isOpen( [[int_(type)|int]] channel )
|Check to see if the specified channel is open
|-
|open( [[int_(type)|int]] channel )
|Opens the specified channel to allow for listening. The channel specified must be larger than 0 and less than 65535.
|-
|close( [[int_(type)|int]] channel )
|Closes an open channel to disallow listening
|-
|closeAll( )
|Closes all open channels
|-
|transmit( [[int_(type)|int]] channel, [[int_(type)|int]] replyChannel, [[string_(type)|string]] message )
|Transmits a message on the specified channel
|-
|isWireless( )
|Returns true if the modem is wireless; false if it is wired.
|}
==Sending Messages==
Sending messages is simple and does not require that you open any channels. Simply use the transmit function like so:
<span>
local modem = peripheral.wrap("right") --Wraps the modem on the right side.
modem.transmit(3, 1, "Hello world!")
</span>

What did that do? First I wrapped the peripheral in order to interact with it. Second, I used modem.transmit(channel, replyChannel, message) in order to send my message. In case you were wondering, the reply channel is captured by the listening computer and suggests which channel they should reply on.

==Receiving Messages==
Receiving messages requires that you be familiar with events. As of this moment, there is no api which cuts out events from the process. Here is an example of how to receive messages:
<span>
local modem = peripheral.wrap("left")
modem.open(3)--Open channel 3 so that we can listen on it
local event, modemSide, senderChannel,
replyChannel, message, senderDistance = os.pullEvent("modem_message")
print("I just received a message from: "..senderChannel)
print("I should apparently reply on: "..replyChannel)
print("The modem receiving this is located on the "..modemSide.." side")
print("The message was: "..message)
print("The sender is: "..senderDistance.." blocks away from me.")
</span>
So what did I do? Quite simply, I called os.pullEvent() with the string argument "modem_message", which blocks all other events from being returned. When the "modem_message" event is captured, it returns the arguments: event, modemSide, senderChannel, replyChannel, message, senderDistance. I captured these and then printed them out.

==Keep in Mind...==
* You can only open 128 channels at any given time.
* The max channel you can open is 65535.
* You can listen on more than one channel at a time. For example, if I have channel 3 and channel 5 open and somebody sends a message on channel 5, I will still receive it. If they send a message on channel 3, I will receive that.
* Sending messages does not require you to open any channels prior to sending it.
* If you aren't receiving a message when you think you should, check to make sure that you have opened the channel first!
* Modems and channels are not secure! If you are sending a message over rednet, it is available to any computer listening on the sent channel.

[[Category:APIs]]

Category:User Created Peripherals

2013-03-21T14:16:31Z

Rihlsul: Just adding this Category to Peripherals so it's more readily find-able.

This category lists notable peripherals created by the ComputerCraft community.

[[Category:Lists]][[Category:Peripherals]]

Os.setAlarm

2013-03-04T17:43:53Z

Rihlsul: /* Explanation */ fix function call

{{lowercase}}
{{Function
|name=os.setAlarm
|args=[[float (type)|float]] time
|api=OS
|returns=[[Table_(type)|Table]] alarmID
|addon=ComputerCraft
|desc=Adds an alarm which will fire an "alarm" event at the specified Minecraft world time. The returned table acts as a unique ID for the alarm.
|examples=
}}
== Explanation ==
([http://www.computercraft.info/forums2/index.php?/topic/5599-ossetalarm/page__view__findpost__p__46168 Forum Post] by jag_e_nummer_ett:)

<code>
--(( Basic format ))--
os.setAlarm(time)
--(( Will timeout when it's 18 o'clock in the world ))--
os.setAlarm(18.00)
--(( Will timeout 2 (in-game) hours later ))--
os.setAlarm(os.time()+2)
--(( Basic event layout ))--
local ev,p1 = os.pullEvent("alarm")
--(( Event output ))--
Name: alarm
Parameter 1: A table that acts like it's unique ID
</code>

== Example ==
([http://www.computercraft.info/forums2/index.php?/topic/5599-ossetalarm/page__view__findpost__p__46167 Forum Post] by MysticT):

<code>
local alarm = os.startAlarm(5)
while true do
local evt, arg = os.pullEvent("alarm")
if arg == alarm then
print("It's 5:00, wake up!")
end
end
</code>

[[Category:Lua_Core_Functions]]

Os.setAlarm

2013-03-04T17:26:55Z

Rihlsul: Added some explanation/example from a forum post, since usage was unclear at best.

{{lowercase}}
{{Function
|name=os.setAlarm
|args=[[float (type)|float]] time
|api=OS
|returns=[[Table_(type)|Table]] alarmID
|addon=ComputerCraft
|desc=Adds an alarm which will fire an "alarm" event at the specified Minecraft world time. The returned table acts as a unique ID for the alarm.
|examples=
}}
== Explanation ==
([http://www.computercraft.info/forums2/index.php?/topic/5599-ossetalarm/page__view__findpost__p__46168 Forum Post] by jag_e_nummer_ett:)

<code>
--(( Basic format ))--
os.setAlarm(time)
--(( Will timeout when it's 18 o'clock in the world ))--
os.setAlarm(18.00)
--(( Will timeout 2 (in-game) hours later ))--
os.setAlarm(os.clock()+2)
--(( Basic event layout ))--
local ev,p1 = os.pullEvent("alarm")
--(( Event output ))--
Name: alarm
Parameter 1: A table that acts like it's unique ID
</code>

== Example ==
([http://www.computercraft.info/forums2/index.php?/topic/5599-ossetalarm/page__view__findpost__p__46167 Forum Post] by MysticT):

<code>
local alarm = os.startAlarm(5)
while true do
local evt, arg = os.pullEvent("alarm")
if arg == alarm then
print("It's 5:00, wake up!")
end
end
</code>

[[Category:Lua_Core_Functions]]