nuxx.net
Making, baking, and (un-)breaking things in Southeast Michigan.

RS232 to Eaton Leonard Interface Prototype

May 22, 2007

Completed Prototype PCB

Well, after about five hours of working this evening (after laying out the board in free time at work) I’ve finished the prototype PCB for the project I’ve been working on for a friend’s company.

As with the last few boards I’ve done, I etched it in the laundry room, as the laundry tub and large flat surface makes for a good place to work. (Photo of PCB being exposed.)

Then I drilled the board, breaking more PCB drill bits than I like to. Next came manual bridging of vias (which is a really awful chore), and then finally assembly. After I had it put together I powered it up, probed around for shorts, and generally confirmed that it wouldn’t explode.

Tomorrow I’ll confirm that the pinout of the board is as expected, and hopefully I’ll be able to deliver it at lunch time. If it works I’ll (hopefully) have some production boards made for them. I stayed late at work avoiding traffic and worked up a first draft of a mostly-SMT board layout, fitting in ~30mm x ~85mm. If I end up producing these boards I can see the final product being something like this, should I choose to do it SMT.

Hopefully tomorrow I’ll get to unpack the new baking stone, the new x0xb0x kit, and maybe just relax a bit. For now it’s bed time. Goodnight.

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HMLiberator Assembled

May 18, 2007

First HMLiberator Assembly with Honda Music Link

Well, there’s an assembled version of the first HMLiberator, strapped to the top of a Honda Music Link. This is very similar to what the final assembly will look like, except the ISCP connector will not be soldered on, the part will be encased in shrink tubing, and there will likely be slightly different cable / connectors used.

I still have a good ways to go on the software. If connected it’s possible to use all controls on the iPod to play music and hear it through the stereo (the initial goal), but I still have to address the following things:

· iPod does not pause / power off when vehicle is powered off.
· HML continues charging iPod while vehicle is powered off. (HML’s software is hanging and not cutting power to the iPod.)
· Attempting to change track on the head unit hangs the HML. (I think it’s not getting the response it desires.)

I think most of these are just a matter of getting the false polling mode, track change responses, and things like that working. After I get back from up north (and get the serial level converter prototype made) I’ll put together another serial sniffer and get back to work on the software.

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HMLibeartor v1.0 PCBs Have Arrived

May 16, 2007

HMLiberator v1.0 PCB complete, except for cables.

Well, the HMLiberator v1.0 PCBs arrived today from Advanced Circuits. (Top and Bottom at 600dpi.) They came in a rather large box which can be seen in the photo in this post. The size of the box seemed to matter, though, as not only did it contain the wrapped stack of PCBs, it also contained a t-shirt, sticky notes, and a bag of microwave popcorn.

I got the first board fully assembled, with the SMT stuff taking a bit longer than normal, although I found that it wasn’t too bad. Things must have gone at least partially right because once I connected the programer to do a test-write with some random copy of the firmware it wrote successfully.

Since Danielle just got here we’re going to grab food and watch a movie. Tomorrow I’ll test the voltage regulator, add the header cables, and connect it to the car for the first time. Hopefully it’ll work. :)

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My Office

May 16, 2007

(Cross posted from YakYak…)


Here’s my desk / office at home taken with an 8mm fisheye lens. You can just barely see the door and G5, which are in opposite corners of a 12′ x 12′ room.

That’s exactly how it is now, except I’ve opened the just-received-before-photo box from Advanced Circuits. (They are the prototype PCBs for a project I’m working on.)

Click on the image to make it full size…

(And please ignore all the wacky flare. It is a fisheye with a 47W diffused daylight CF near the edge.)

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FibraMent

May 16, 2007

I just ordered a FibraMent baking stone to replace mine which was broken on Friday while extracting a pizza from the oven.

I purchased the 13 3/8″ x 17 1/2″ version, which is US$50 shipped. It should fit nicely inside the oven and provide a (hopefully better than before) platform for baking of bread and pizzas. The stone I had before was around 3/8″ thick, and this one is 3/4″.

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Electronics Help: Current Loop

May 14, 2007

Staying late at work today I set about turning this PCB into this schematic. (I also replaced the MC1488 / MC1489 combo with a MAX232, eliminating the need for a bunch of diodes and feeding the board +/-15VDC.)

It supposedly turns RS232 into current loop, where amperage is used to signal 0 or 1 instead of voltage. This makes the signal more robust in noisy environments or with long wire runs.

The thing is, when I look at this, I can’t quite see it as being anything more than a device which takes RS232 serial and converts it to be 0V or 30V (for low or high), and optically isolates data going back to the PC. I don’t see any way it actually varies the amperage while keeping the voltage steady.

Can someone correct me, or confirm what I’m seeing? The schematic, as made from the board, is here.

(Also, I need to remove the 7486 part. Each currently grounded leg of the gate was originally set to a jumper to select if it should be high or low, but the needs of this board are fine having them all grounded. As it’s XOR on all of them, and one leg is always pulled low, the output will always be whatever the input is. So, I think I can eliminate the 7486. I believe the jumpers serve to invert the signal, should it be needed. But it’s not. And I didn’t remove the 7486 while removing the jumpers because I wasn’t certain of it was used for anothing else. But now I know. And knowing is half the battle.)

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Oak-y!

May 11, 2007

French (Toasted) Oak Chips Soaking in George Dickel

As part of making the Simcoak (which I hope comes out good) I’m soaking around 4.75 ounces of toasted French oak chips in a pint glass of George Dickel bourbon. Sure, that’s almost $10 of bourbon, but I’m hoping that it’ll sanitize the chips, contribute to the flavor of the beer, and leave me with some still-good, drinkable, extra-oaky bourbon afterwards.

Also, Danielle and I made pizzas tonight. Below the cut is a picture of the better looking of the two pizzas.

Click for pizza picture!

beerfoodmoved from livejournal

Dr. Bronner’s Peppermint Pure Castile Liquid Soap

May 10, 2007

(Click for full size image…)

Oh, I also (finally) replaced the Dial-branded pump soap dispensers which I’ve had in the bathrooms since I bought this place with something nicer. The old dispensers weren’t dirty or worn out, but I was fairly tired of the smell and anti-bacterial-ness of Dial soap. The cheap, prone-to-toppling dispensers were a bit of a bother too.

Stopping at Trader Joes on the way home I picked up a bottle of Dr. Bronner’s Liqiud Soap, in Peppermint. At US$8.99 for one quart it’s not very cheap, but it is very nice soap.

Also, don’t forget to read about E. H. Bronner‘s colorful, driven personality.

acquired thingsaround the housemoved from livejournal