My eyes burn!

[dknguyen]

Mann. I only got 3 hours of sleep last night because we were trying to get our firmware to work for our design project. We had it almost working excpt for some reason to get the feedback to graph properly we had to reboot the PIC after the GUI had instructed the PIC to start. THat wasn't good enough so we tried to fix it but didn't do version control. So we spent the next 12 hours trying to get back to the point we were at and never quite made it.

In the lab until FREAKING 3am and presentation today from 9-2 and we have not practiced it becase of the firmware.

Also our PCBs had manufacturability problems we realized too late so we can't actually demo our thing on a real oven (it's a reflow oven) since we can't pass 120V@15A on a breadboard so we hvae to use all sorts of simulated power supplies for the AC mains and can't actually get the output to affect the input since no oven is present.

And my eyes still buurn from last night! OW. 12 hour days for the past 2 weeks. ACk. Stupid PCBs.

 

[killivolt]

In the lab until FREAKING 3am and presentation today from 9-2 and we have not practiced it becase of the firmware.

Cat naps even 15 min close your eye's refresh if only for that amount of time. It can help the thinking process good luck.

 

[Marks256]

Good luck, dknguyen. Let us know how it goes.

Good advice with the 15 minute cat nap. I haven't been getting much sleep lately, either.

 

[Hero999]

I don't know how you do it. I find it hard to not fall asleep at work if I've had anything less than 8 hours sleep. Sometimes I sneek off to the store room to have a half an hour nap so I don't fall asleep at me desk.

 

[3v0]

Most of us have been there. Good luck.

 

[JimB]

WORKING!!!!

This will just not do!

You should post here with a "Plz help URGENT with projkt" thread

Good work, keep at it and dont give up until the fat lady sings!

JimB

 

[killivolt]

Good work, keep at it and dont give up until the fat lady sings!

Make that old girl hit key's she never thought she could.

 

[dknguyen]

Well, we were able to get something for a demo working
THe problem was our microcontroller hit brick-wall 100% verify fails with multiple chips and multiple programmers (in-circuit and socket) so we had to switch up at the very last minute and redevelop our firmware.

THe second big thing was we chose to etch our dual-layer PCBs in house and not send it away to a company. But you can't get thru-plate holes and so the boards ended up being non-assemblable and we had no time to get new ones. Seeing as how our project is a 120V, 15A oven driver we could not close the control loop on a breadboard without and as a result had to do the demo on a breadboard and just used the oven as a temperature input and showed how the output responded (but not tracked) the input. THe firmware was a pain because it was built up on legacy because the members championing the alternate processor didn't know it's structure very well so the code was all bogged down in legacy from as they were learning it and building on it. You could a line of code form one area that would simply turn a pin high to another area and it wouldn't work in that new area (which all the lines of code in that area ran just fine before this line was added).

We had to scrap 3 of our subsystems that could not be prototyped and had to present last after many other groups with nice finished PCBs, and enclosed packaged projects. We seemed to be the only one with a GUI though.

We arranged and worded the slides very carefully to try and deflect our lack of a finished product to our knowledgability. We tried to cut off all possible obvious and simple questions by answering them during the presentation so the graders would have no choice but to ask strange obscure questions which we knew we could answer and maybe shine during question period instead. Some of the graders obviously weren't listening since they kept asking questions and I had to keep referring back to stuff I clearly described earlier on. It gets old when you have to keep pointing back to previous points 3 or 4 questions in a row.

It's easy to make a presentation when you have a perfect product. Try making a presentation when you have nothing after everyone else's perfect product presentations.

The only good part was how everyone was dressed up in their best formal business-ish clothes. Yup. GIrl engineers know how to dress up better than anybody else on campus. They looked so good I wanted to poke out my freakin eye's. THat definately woke me up when I got there.

I just might get through university without ever having a cup of coffee or pulling an all nighter.

 

[jpanhalt]

Good story. Congratulations. It's a rite of passage. A lot of us have been there and have plenty of stories to tell. We had one girl in chemistry. No one ever noticed her, until she got dressed up for a party. Wow. Unfortunately, that didn't happen very often. John

 

[Hero999]

THe second big thing was we chose to etch our dual-layer PCBs in house and not send it away to a company. But you can't get thru-plate holes and so the boards ended up being non-assemblable and we had no time to get new ones.

So solder a piece of tinned copper wire through the vias.

 

[dknguyen]

So solder a piece of tinned copper wire through the vias.

The vias aren't the problem. It's the fact that you have to solder on the side with the trace which doesn't work with most of the power components including power resistors, relays, terminal blocks, transformers, capacitors, etc.

 

[jpanhalt]

The vias aren't the problem. It's the fact that you have to solder on the side with the trace which doesn't work with most of the power components including power resistors, relays, terminal blocks, transformers, capacitors, etc.

That's where those little rivets can come in handy. I got mine from Circuit Technology (circuittechctr.com) . That's an old address. I use the 0.036 I.D. ones, which is just a little bigger than my usual drill. Larger and smaller sizes were available. Insert the rivet. Solder to the trace on top. Insert the TH component, solder on the bottom to the rivet. You don't need the expensive squeezer they sell. Just use a conical punch for the shop-formed end and something flat for the pre-formed end. However, many times, if you have a good pad on top and tight fit, you don't need to flare them. John

 

[3v0]

The boards should not have been a problem.

I etch a few DS boards. During layout do not use a pad as a via when you can not solder both the top and bottom. (sounds like you found this out the hard way) Solder short bits of wire into the vias and make sure you solder pads used as vias both top and bottom.

For signal traces you may be able to place a strand of thin wire in the offending hole along with the component lead and bring it out to where it can be soldered.

It would be handy to have a few of the rivets John mentioned to fix goofs or if one wanted to etch a board intended for plated through holes. I used to have some.

 

[killivolt]

Solder short bits of wire into the vias and make sure you solder pads used as vias both top and bottom.

For signal traces you may be able to place a strand of thin wire in the offending hole along with the component lead and bring it out to where it can be soldered.

Working with R&D it was my task to perform these counter measures. (They work) I have not had the opportunity to use rivits (But sounds like a good idea.)

When needed use the small wire with insulation sometimes we had it going everywhere. Even on prefab.

 

[Hero999]

The vias aren't the problem. It's the fact that you have to solder on the side with the trace which doesn't work with most of the power components including power resistors, relays, terminal blocks, transformers, capacitors, etc.

You could leave the pins a bit too long and use a fine soldering iron to solder on the component side.

You might also be able to rely on the pins to conduct enoguh heat to melt solder applied to the other side of the board.

 

[kjennejohn]

Yeah, you have my sympathies.
I was the only tech in my company in the new products line. Showing up at a tech training meeting for paying customers was a command performance. In the middle of my first presentation, someone asked a question that only a tech drawing could answer. I was using an overhead projector shining on one of those old pulldown movie screens. I had no blank transparencies to scribble on, so I simple grabbed a magic marker and started writing on the screen... no, wait, is this a good idea?! It got some good laughs, and the hotel who owned the room and the screen sent one of their techs up to clean the screen right away. After that, I knew to have blank transparencies at these things.

Ah, yes, all nighters. That ended at my last job after it was discovered that I had a sleep impairment and had to be wearing a mask attached to a machine when I slept. No more rolling under a desk on a sleeping bag for a cat nap. It got to midnight and I was out of there.

Take care.
kenjj