[FRC Blog] myRIO Expansion Port - What's the Deal?

[SoftwareBug2.0]

Originally Posted by crake

Well you don't HAVE to use anything. There are a lot of tools out there for creating schematics and layout. The NI tools however offer that, plus a lot more, including simulation. If you're going into electrical engineering (particularly analog design), SPICE is a really valuable tool.... and you get it for free! Also the template for the board outline is already loaded for you.

Well certainly; I don't have to use the MXP port at all. And if National Instruments wants to provide a simulator and a board layout tool then that's fine too. But these things shouldn't have to be connected. Perhaps there's a link someplace I've missed but it looks like if you want any more than the voltage range and intended use you must use SPICE. For example, how many amps can I draw on each of the pins? What are the supported speeds of the serial port? These should be easy to spell out in text. I should not have to run a simulation to find out.

I agree that SPICE is useful. It's just not clear to me how the MXP port would cause you to use SPICE if you'd been given a proper data sheet. If I'm speccing a filter a simulation is great to go along with the graph for what the cutoff is supposed to look like. But in the MXP port there should't be anything interesting analog wise: everything is either digital, straight to an ADC, or straight to a DAC. And I doubt that the digital stuff is fast enough that the use of SPICE is warranted.

Originally Posted by crake

Yes, you can, and calling out backside clearance does not replace the need to do a good job on the stack up analysis and mechanical tolerance calculations. However it does remind people that the default board position offers limited backside space, and if you want backside components, or long through-hole leads, etc. you will need to move to a taller connector.

Do people actually screw this up? There is something to be said for making documentation accessible but please assume that high school students have mastered the ruler.