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A user asked for help on a circuit .. this is the result .. this is a good example of how to use subcircuits, and the power of Spicy. 

OK, here is how you do it: 

The basic idea is, we make a circuit, we get the netlist, and we make a subcircuit out of that ... 

Start with the logic diagram: http://prntscr.com/2sbj2g

Make this circuit in Spicy: 

Notice you need XOR, which is not a standard part, but there is an XOR model on the Spicy models page: http://ischematics.com/validModels.py, We can use this model for XOR ... in the new version of Spicy you can make custom symbols and so there will be a lot more parts very quickly, but in this older version if there is not a standard symbol for a part, you have to use a subcircuit box ... it works the same ... you place a subcircuit symbol, and you set the value to the name of the model .. in this case the XOR parts are set to this model: http://ischematics.com/validModels.py?MODEL=LOGIC_XOR

I first make the basic portion of the circuit, two inverters and an XOR: http://prntscr.com/2sbk2v
I wired them up also

Now, select and copy that 5 times .. you need 6 of those ... note that when you copy, you have to click the select button, drag a box around what you want to select, then click copy, then you drag the new copy into position: http://prntscr.com/2sbkpk

Now duplicate the XOR subcircuits by clicking on them, and then clicking duplicate: http://prntscr.com/2sbkv9, you need 3 of them at the next level

You should now have something like this: http://prntscr.com/2sbl76
only partial schematic shown ... use the scroll menu on top right to move around .. 

Once you are done adding parts, add ports so that you can name the inputs and outputs, like this: 
http://prntscr.com/2sbmt6

Actually if you name ports with an underscore then number at the end, starting with _0, when you copy them they will be renamed nicely in order ... 

OK, now, i created the circuit, and uploaded to the Spicy online circuit library (OCL) .. you can click the OCL tab, clecik Clear Fields, then enter "parity" and click search ... 
http://prntscr.com/2sbpi0

you will see a button to import the circuit .. do that and you will have the circuit i just made

Now, notice i added a voltage source .. .this is required by Spicy because it thinks you want to simulate it and it has to be 5V because it is a logic circuit .. but since we are only wanting to make a subcircuit, we will remove it from the netlist .... 

The netlist is attached as generated by Spicy. 

Now, to make a subcircuit, you need to create a subcircuit definition using spice syntax ... in the older version you had to do this manually, and in text by uploading the model on our website (go to Model Upload from the ischematics.com homepage)

I created this subcircuit called PARITY and uploaded, you can see it here: 
http://ischematics.com/validModels.py?MODEL=PARITY

To learn about subcircuits, see here: http://newton.ex.ac.uk/teaching/CDHW/Electronics2/userguide/sec2.html#2.4

Now, we are almost done .. to use the subcircuit, just make a new schematic and place a subcircuit part, define the inputs and outputs, and set the value to PARITY (the model name) ... 

This shows me specifying the input names, and output names for the subcircuit: 
http://prntscr.com/2sbr61, and Here is the value of the subcircuit: http://prntscr.com/2sbrcp

Once you do that .. this is what you get: http://prntscr.com/2sbrh4



That is the full integrated circuit in one part, ready to use!!

Let's test it .. .since it should give odd and even parity outputs depending on inputs, let's try one for each case ... if i ground all inputs, i should get even parity .. i will simulate transient for 1ms

Here is with all inputs grounded: plot: http://prntscr.com/2sbsy0

Here is with one input high: Schematic: http://prntscr.com/2sbt5c, plot: http://prntscr.com/2sbt9f

So there you go! A custom subcircuit made from a datasheet, made into an IC part in Spicy, and simulated .. 

Spicy is very powerful, but I can see how this example shows how clunky the old interface is .. we developed the new one over the past year to make all this much much easier .. it will be available very soon. Until then I hope this example helps you. You can see how poweful this can be, when building up larger circuits with subcircuits. The new version makes this much easier and quicker to do. 
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Played with Spicy today on a HUGE mac monitor at best buy ... very cool ... the new all-in-one touchscreen PCs with large monitor offers new possibilities for Spicy and for circuit design! 
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New Video on our YouTube Channel, How to Make Wires:  http://youtu.be/7P5UMFph8Pk
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fyi, we have two new libraries of examples in the Online Circuit Library within Spicy .. There are buttons there to open them easily and you can download the circuits .. note that this is available now on Spicy for web, but not yet in the ipad version, we are waiting for Apple to approve the latest release
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Spicy 3.0 is coming!

We have been working hard to provide a new interface that is easier to use ... we have added new features and enhancements, like a combined 2-axis current and voltage plot so you can see all your signals on one screen, and faster operation with less memory usage .. 

Look for this update coming soon!

http://ischematics.com/images/ex_spicy3_3.0.png
http://ischematics.com/images/ex_spicy3_4.0.png
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Spicy Schematics and Spicy SWAN v2.4.6 available now on web and for ipad on the app store. Update today!  Includes minor bug fixes and new features including the ability to now set the .OPTIONS line properties in spice!
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FYI, on Spicy for Web, you can now set some of the .OPTIONS line parameters for spice simulations.  Some circuits converge better with RSHUNT or GMIN specified differently for example, and you can also choose the integration method of GEAR or TRAP .. defaults are TRAP, RSHUNT off, and GMIN=1e-12 and you can select the default as well.  This is available now on Spicy for Web, and will be available on ipad for the next release coming soon.  
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Ok, so with Spicy Schematics you have everything you need for circuit schematic design and simulation with professional-grade spice, ... but what if you need to do high speed digital simulations, with hundreds of RC networks?  How about transmission line calculations that you need to run at the speed of light? TDR anyone? Spicy SWAN is our new professional version of Spicy and uses the power of Digital Wave Network (DWN) DSP techniques using the revolutionary Simulation by Wave ANalysis (SWAN) engine!  Check out Spicy SWAN at our website:  

http://ischematics.com
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Congratulations Spicy, we now hit 200 FB likes! Thanks everyone ... remember if you like Spicy, please help by posting a good review on itunes .. it helps us support development of the app .. we have only a handful of reviews and most of the time from the few who wanted something else and were not happy ... but 200 FB likes means maybe we can get 200 good reviews on itunes! That would help us out a lot ... just go to itunes, search ischematics.com, and you can review the free, or full or now swan versions, which ever you like .. (or review all if you like) ... :)
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Website re-do!  Check out our new homepage look!  This comes as Spicy version 2.4.2 is coming out soon, and Spicy SWAN on the way! Also note that our Spicy Circuit Simulator iPhone utility has a whole new look ... Look out for the coming updates with many new features!
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Spicy Schematics, Circuit Schematics and Spice Simulation for iPad, iPhone
Introduction
SPICY Schematics is a revolution in electronic circuit schematic capture

Spicy takes full advantage of mobile and web technologies for circuit design - the first tablet application to offer real Spice simulation and advanced sharing and online backup features for iPad and Web.

SPICY is fast, intuitive, and allows you to literally draw circuits with your fingers. Create, save, edit, share, simulate, export and send screenshots to email, SPICY is a must have for students and working engineers alike.