\end_layout

\begin_layout Paragraph
FIRENET/CHANNEL
\end_layout

\begin_layout Standard
This command is used to read out the A/D value on a particular channle of
This command is used to read out the A/D value on a particular channel of
 a node.
\end_layout

\begin_layout Standard
\begin_inset Tabular
<lyxtabular version="3" rows="2" columns="3">
<features tabularvalignment="middle">

\begin_deeper
\begin_layout LyX-Code
"shows" : [
\end_layout

\end_deeper
\begin_layout LyX-Code
		{ "show"		:	"La Mariseillaise",
		{ "show"		:	"La Marseillaise",
\end_layout

\begin_layout LyX-Code
		  "file"		:	"mariseillaise.json",
\end_layout

\begin_layout LyX-Code

\end_inset
</cell>
<cell alignment="center" valignment="top" topline="true" bottomline="true" leftline="true" rightline="true" usebox="none">
\begin_inset Text

\begin_layout Plain Layout
No data, only one referant
No data, only one referent
\end_layout

\end_inset
</cell>
</row>
</lyxtabular>

\end_layout

\begin_layout Standard
This is the command to start the show.
 If the show has been SET then this will start by syncing the nodes, then
 starting the music file and startthe programmed firing sequence in the
 starting the music file and start the programmed firing sequence in the
 nodes.
 The user has to have armed the nodes before sending this command.
\end_layout

\begin_layout Standard
\begin_inset Tabular
<lyxtabular version="3" rows="2" columns="3">

\begin_inset CommandInset citation
LatexCommand cite
key "HTTP"

\end_inset

 is very well suited for this task.
 It is small, selfcontained and is designed to be added into applications.
 It is small, self contained and is designed to be added into applications.
 
\end_layout

\begin_layout Standard
In addition a JSON parser has been added to support data sent in this form.
 JSON messages out are easily generated using formatted write statements
 in Lua.

\begin_layout Standard
As you can see this is an instance class and you may use the request handle
 as the selector to pick the method (close()).
 Either form is acceptable.
 This is used to return the result of a RESTful request to the client.
 The data is usually encoded as JSON and will available to the client.
 Also the request data (from http.open() is reclamed.
 Also the request data (from http.open() is reclaimed.
\end_layout

\begin_layout Paragraph
http.url(h)
\begin_inset Index idx
status open

\end_inset
</cell>
<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
\begin_inset Text

\begin_layout Plain Layout
Restart noad software
Restart node software
\end_layout

\end_inset
</cell>
</row>
<row>
<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">

\end_inset


\end_layout

\begin_layout Standard
This command will fire a selected circuit in the node immediatly.
This command will fire a selected circuit in the node immediately.
 The node will be out of communication till the firing cycle is over.
 The available firing channels are numbered from 0-5.
\end_layout

\begin_layout Labeling
\labelwidthstring 00.00.0000

\end_inset


\end_layout

\begin_layout Standard
This is similar to the firing command but will fire the selected ciruit
This is similar to the firing command but will fire the selected circuit
 at the specified time.
 All nodes keep a 32 bit millisecond counter.
 The Z command (see 
\begin_inset CommandInset ref
LatexCommand vref
reference "par:SYNC"

) will sync the time for all the nodes, also it will start the node cycling
 through the queue firing the events in time order.
 The available firing channels are numbered from 0-5.
 The command takes a single byte firing circuit value and 32 bit  time value.
\end_layout

\begin_layout Description
P316543 Store firing command for circuit 3 at 16,543 miliseconds.
P316543 Store firing command for circuit 3 at 16,543 milliseconds.
\end_layout

\begin_layout Standard
This command is ignored if sent to the broadcast address.
 There is no response immediately
\end_layout

\begin_layout Standard
When the node fires it returns RP<ch #> allowing tracking of the autofiring.
When the node fires it returns RP<ch #> allowing tracking of the auto firing.
 
\end_layout

\begin_layout Paragraph
STATUS
\begin_inset Index idx
status open

 queue
\end_layout

\begin_layout Standard
Testing of the sync command with a script that syncs the nodes then has
 them fire at the same time shows the following spread in 10 runs with 3
 nodes, (4,5 and 6).
 Then monitering the firing time of channel 0 and using that to trigger
 Then monitoring the firing time of channel 0 and using that to trigger
 a scope, it captured each of the nodes firing.
 Measuring between the first firing node and the last we get the following
 spreads in 10 trials.
\end_layout

\begin_layout LyX-Code

V Query node code creation date
\end_layout

\begin_layout Standard
This message is used to get the creation date of the code running in a node.
 The message returned is a string of the compiler constants __DATE__ and
 __TIME__ which shows the creation date of the code.
 This is ment to be human interperted and not machine used.
 This is meant to be human interpreted and not machine used.
\end_layout

\begin_layout Paragraph
CHANNEL
\begin_inset Index idx
status open

Network 
\end_layout

\begin_layout Standard
The network hardware is ISL8483 RS-485 chip.
 The transmit and receive lines are brought out to pads where they will
 be connected to two stereo phone jacks (one in and the other out).
 The network will be like that show in Section 
 The network will be like that shown in Section 
\begin_inset CommandInset ref
LatexCommand vref
reference "sub:Physical-Layer"

\end_inset

 .

 is being sent.
 On the control computer (UNIX/LINUX) the serial output data is handled
 via a system driver.
 The TRANSMIT control line was the DTR line in the serial interface.
 It was found that the DTR ON/OFF signal was very deterministic and would
 occur at the exact line of code where it was called.
 Unfortunately this was NOT the case with the serial data.
 It went into the driver and when exactly it came out was highly dependent
 on the OS system loading and other factors.
 So to make the XMIT control ON/OFF properly overlap the actual data the
 code had to:
 It went into the driver and when exactly it came out the serial port was
 highly dependent on the OS system loading and other factors.
 To make the XMIT control ON/OFF properly overlap the actual data the code
 had to:
\end_layout

\begin_layout Itemize
Turn on DTR
\end_layout

\begin_layout Itemize

\begin_layout Itemize
Turn off DTR to close the transmit.
\end_layout

\begin_layout Standard
This would work about 90% of the time but occasionally the control program
 would be swapped out and the disable of the XMIT would be very very late.
 Then the control computer's transmit would be enabled while a node was
 trying to reply.
 This greatly affected actions where there was a lot of message between
 the control computer and nodes (like programming a show).
 Then the control computer's transmit would still be enabled while a node
 was trying to reply.
 This greatly affected actions where there was a lot of message traffic
 between the control computer and nodes (like programming a show).
 
\end_layout

\begin_layout Standard
The solution was to put control of the TRANSMIT ON/OFF in the network interface.
 The board used in the interface is a modified node board so instead of
 just the interface chip the Atmel processor was added also.

\begin_layout Standard
The blue line at the top is the transmitter control signal, the the two
 waveforms are the RS485 signal and compliment signals.
\end_layout

\begin_layout Standard
The board is programmed as an Arduino with the main serial interface attached
 to the control computer (see the progam HeadEnd in the Arduino code section).
 The Arduino project has a library so add a second serial port on an I/O
 pins.
 That then is used to go to the FIRENET network as shown above.
 to the control computer (see the program HeadEnd in the Arduino code section).
 The Arduino project has a library that adds a second serial port on any
 I/O pins.
 That software serial port is used to connect to the FIRENET network as
 shown above.
\end_layout

\begin_layout Standard
The only change in the FIRENET control program is that it no longer switches
 DTR when it transmits a packet, all that is handled in the network interface
 board.
\end_layout

\begin_layout Subsubsection
Firing Circuit
\end_layout

\begin_layout Standard
The firing circuit includes the 1 Amp constant current regulator, a relay
 and 6 FET drivers.
 IC5 (7812) is wired to produce 1 Amp output for loads down to 0 ohms.
 This current is switched by a relay (RLY1) so the firing circuits are OFF
 except when needed.
 This current is switched by a relay (RLY1) so the firing circuits are completel
y OFF except when needed.
 The 6 FETs (QF0-QF5) are wired as simple switches so when the processor
 makes the gate high the FET goes to low resistance.
 The Fireworks ignitor is wired between the CC supply and the FET drain
 so up to 1 A flows firing the piece.
 The resistor divider off the drain is used to feed the voltage value present
 on the drain to the processor A/D.
 If the transistor is OFF this will be the full voltage of the battery.

reference "par:TIME-Command"

\end_inset

).
 The firing time can now be set to a maximum that will guarantee that ANYTHING
 will be fired.
 We them monitor the continuity during the firing and turn off the firing
 We then monitor the continuity during the firing and turn off the firing
 channel when the ignitor blows.
 
\end_layout

\begin_layout Standard
We cannot measure the continuity while the FET firing transistor is ON so
 while the ignitor is being fired the transistor is switched off for a milliseco
nd.
 The software reads the A/D for that channel and if the ignitor is blown
 it will show a low voltage since the ignitor binding post is no longer
 connected to the firing voltage (HOT1/HOT2).
 If the ignitor is not blow there will be a connection and the A/D will
 If the ignitor is not blown there will be a connection and the A/D will
 read a high voltage.
 Thus as soon as the ignitor is blown we can cut off the FET firing transistor
 and stand down from the firing state.
\end_layout

\begin_layout Standard
There are some considerations for this testing, it should be often enough
 to stop the firing reasonable early.
 to stop the firing reasonably early.
 That is if the max firing time is 3000 ms testing at 2000 ms intervals
 wouldn't be too useful in ending early.
 On the other hand testing too often at say 1 ms intervals would not let
 On the other hand testing too often at say 10 ms intervals would not let
 the ignitor heat up as we would be turning off the firing FET at very frequent
 intervals.
 So testing was done to try to determine some reasonable values, testing
 at 100 ms intervals seems to be a good balance between ending early and
 not heating the ignitor enough.
\end_layout

\begin_layout Subsubsection
Processor
\end_layout

\begin_layout Standard
The processor circuit is largely copied from the Arduino board.
 The serial, reset and power leads are brought to a header which fits the
 SparcFun Serial <-> USB board.
 This can be used to talk to the board for testing.
 This can be used to talk to the board for testing and programming using
 the standard Arduino IDE.
 Also two jumpers are added to allow the USB board to power the board and
 control the network chip JP2,JP3).
 This modified board is used as the control computer interface to the network.
 
\end_layout

\begin_layout Subsection