Friday Hack Chat: Trusting The Autorouter

Ah, the autorouter. Inside every PCB design tool, there’s a function called the ‘autorouter’. This function, when used correctly, is able to automagically lay traces between pads, producing a perfect board in under a minute. The trouble is, no one uses it. We have been told not to trust the autorouters and we hear a lot of other dire warnings about it. The autorouter never works. The autorouter will put traces everywhere. The autorouter doesn’t consider floorplanning, and sometimes you’re going to get traces that go right through the edge of your board. Is avoiding the autorouter sound advice?

For this week’s Hack Chat, we’re talking about trusting the autorouter. The autorouter is just a tool, and like any tool, it will do exactly what you tell it. The problem, therefore, is being smart enough to use the autorouter.

Our guest for this week’s Hack Chat is Ben Jordan, Director of Community Tools and Content at Altium. Ben is a Computer Systems engineer, with 25 years experience in board-level hardware and embedded systems design. He picked up a soldering iron at 8, and wrote some assembly at 12. He’s also an expert at using an autorouter successfully.

In this Hack Chat, we’re going to talk to Ben about Altium, Circuit Maker, and how to get the best performance out of an autorouter. How do you set the autorouter up? How do you test your settings? What, actually, is the technology and math that goes into an autorouter? What is the best way to design a multilayer board? How do you do multiboard designs? And what’s the deal with mixed signals?

join-hack-chat

Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This Hack Chat is going down Friday, February 23rd at noon, Pacific time. Want to know what time this is happening in your neck of the woods? Here, look at the neat time zone converter thingy.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.

You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.

CircuitMaker From Altium

Altium recently announced CircuitMaker, their entry into the free/low-cost PCB design tool market. They’re entering a big industry, with the likes of Eagle, KiCad, gEDA, and a host of other tool suites. We had a few minutes to talk with Max in the Altium booth at World Maker Faire, and even got a bit of time with the tool itself.

Hands on, it definitely has the look and feel of Altium Designer, right down to the familiar yellow and green boxes for schematic and sheet parts. Center stage was the 3D view, a feature which Altium has had in their software since the late 90’s.

CircuitMaker’s website is pushing the collaboration aspect of the software. Design choices can be reviewed and commented on in real-time. This also suggests that the data files will live in Altium’s own cloud storage system.

CircuitMaker is still in the pre-beta phase, but they’re looking for beta testers now, so head over to the site and sign up!

Apollo Guidance Computer Clone


[Cliff Miller] pointed out this incredible project from 2004. [John Pultorak]’s journey began in late 2000 when he decided to build a 60’s or 70’s era minicomputer. While gathering technical documentation, he found some interesting information on the Apollo Guidance Computer and felt that was the way to go. The AGC was the first integrated circuit computer ever built. Designed by MIT in 1964 it was constructed from ~5000 ICs, almost all 3-input NOR gates. [John]’s version uses late 1960’s 74LS TTL logic which gains him a 10 to 1 reduction in the number of ICs. A good thing when you have to do ~15K wirewrap connections. He also used flipflops and register chips instead of building everything from NOR gates. [John] essentially built the AGC three times: First, he coded a simulator in C++. Then, he imported the logic design into CircuitMaker to verify that it would actually work. Finally, he built the 3 by 5foot machine. He’s provided an amazing amount of documentation for anyone that wants to explore this device and the overview alone is well worth a look.