Friday, June 26, 2009

Kyle University

Okay, I am showing john this great presentation, the first part of it is pretty useless, but once you get down to the demos it has some real juicy information. We went through this presentation with lots of stops to show nuances within labview, and the subtle differences that a labview operator is aware of.

Friday, June 19, 2009


Boy is it hot outside... Glad to get inside, and cooled down.

Haven't made a lot of show able progress today, but I've been going through a lot of FPGA documentation on the Developer Zone on NI's website. Learning a bit more about DMA FIFO memory access, as well as using interrupts. Basically... You compile an FPGA VI to get a specified amount of data from a channel, let's say.. Collect 5 analog samples of a temperature sensor, when it has 5 samples, the FPGA VI, sends it up to the Host VI. Host VI then says, okay, this temperature is out of spec, let's compare it to the last couple values. Okay, it has been out of spec for 6 cycles, therefore, I want to open the cooling valve by Pi()/64 radians, which sends this procedure to a sub-VI that opens the cooling valve a little bit. Once that Sub-VI is done, it goes back to the Host VI, and says, ok, I'm done. The Host VI says, okay, in order for the system to return to steady state from the transient state I just put it in, I need to wait 40 seconds. So... Wait 40 seconds... Then, go back to FPGA VI, and take more samples.. Repeat...

Makes sense to me...


Friday, June 12, 2009

Okay, so the digital LED went well.... but....

I have struggled a bit after getting the digital LED thing going... I thought I was going to jump right into other stuff... As the day wound down, I ended up going with an analog LED VI.. Right around 1.8 volts the LED starts to come on, but is very dim.. After 2 volts, it doesn't really get any brighter, and the rail is like 16volts..

Anyways, here is the VI for it.


Well... Here it is.. Wish I had a video camera to show you, but this is the blinking LED. I put it so it is logic 1 for 500ms, and logic 0 for 500ms, so it blinks on and off once per second.. I thought about going through gyrations of speeding up the blinking light, and slowing it down, or even putting it on a random number generator, but I think I got the premise down, and time to move on to bigger and better things.

Let's see about doing a little digital input!


Friday, June 5, 2009

Another week goes by, and progress it is!!!!

This is what I go so far.. It makes the LED blink on and off like I want, but not at the rate at which I want... I did notice though that when you pull the digital output to ground on the multi-meter, that the voltage is not the logic 5v I expected, but right at the point where its leading edge is high enough to push it into the 1 slot,, 3.2 volts or whatever...