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RS232 to Eaton Leonard Interface v2.0
(Bottom View)

Well, there it is. That’s one of the first pieces of the RS232 to Eaton Leonard Interface v2.0, part of the lot of five I assembled tonight. They are bagged up and ready for delivery so that the customer can test them out before the inital install (at one of their customer sites) at the end of the week. The PCBs were ordered last week as a prototype run and they arrived today, so I got to work as soon as the UPS driver showed up with the box.

Everything went great with the boards, and the v2.0 design meets all its goals. It is simpler than v1.0, easier for me to assemble, uses fewer parts (both count and type), and can be configured to talk to itself. Yep, this one can act as either end of the cable. Thanks to this the jumpers can also be configured so that a simple loopback can be plugged into its EL connector and all the electronics on the board can be tested outside of a production environment. (This makes testing loads easier for me as well.)

So, that’s about it. I’ll be assembling the rest of the first run this week and weekend and hopefully delivering them early next week. Yay!

My partially completed Millett Hybrid Maxed PCB

That right there is what I did tonight… Well, I assembled as much of the Millett Hybrid Maxed PCB I reasonably could. I still have to get a few more parts for the board (headers, fuses, fuse holders, resistors), wash the board, fit a few more parts, build the enclosure, and a few other things. Then it’ll be done.

I also have to send his parts for it, which I’ll do after I get the rest of the parts.

Tomorrow I should received the PCBs for the RS232 to Eaton Leonard Level Shifter v2.0, and I’m going to try and build five tomorrow night. Hopefully they will work, work well, and be acceptable to the customer.

Photos from the beer fest, bricors’ place, and other things coming later. This was a good weekend. :D

Ceramic Caps

Today a received a gigantic box from Mouser containing all the parts for the RS232 to Eaton Leonard Level Shifter v2. This includes over 100 DIP ICs, 110 BC557 transistors, shunts (jumpers), tantalum capacitors, screw terminals, LEDs, 2×3 headers, RJ45 connectors, resistors, and the FETs for current reversal protection.

I also finally bought a lead bender, so that the bends in resistors will be a lot more accurate / consistent.

Assembling these 25 is going to be a chore, but will also be worthwhile. Yay!

Now, to go to Meijer and get extra foodstuffs for the weekend.

SPI Decoder Hackery

Here’s a design I just threw together for a hokey SPI decoder so I can watch what is going on internally in the Honda Music Link. It’ll read both SPI lines and turn it into RS232 data on the PC. Basically, the software on the PICs will just data out of the SPI buffer as it fills (and triggers an interrupt) then write that out the UART. Should work, I think. The only big problem will be the decoding software on the PC.

Anyone want to write up some decoding software for me? It should be easy to do… Just needs to watch a serial port (or maybe both) and decode packets as they come in. Hell, if you can write the framework for it, I can add the decodes as I figure them out.

(The point of this is to basically reverse engineer how Honda talks to CD changers.)

Here is a write-up on ordering extremely cheap PCBs from questionable Chinese PCB fabricator Gold Phoenix Printed Circuit Board Co.,Ltd.

There’s a couple projects I may use them from. I just need to edit some files and decide on a solder mask color. (I’m not designing this myself, just changing the documentation bits of the design slightly.)

There is something odd to me about ordering $50 worth of optocouplers. I’ll be receiving many, many tubes of chips soon. It seems I’ll be making 25 of the v2.0 boards, with at least four (and most likely more, if not all) of them by the end of next week.

Also, who knew that jumpers and pin headers cost so much? Well, at least for RoHS-compliant decent quality ones. <shrug> It all works out in the end, though. Also, it’s a good thing I ordered that hundred pack of antistatic bags.

Now, to finalize the PCB and order it. (I might do that tomorrow, as I can order the boards as late as 9:30am and still get the order in before the salespeople arrive.)

Also, the Clarkston Union has raised their prices. A full order of portabello gratin is now $15.

RS232 to Eaton Leonard Level Shifter v2.0 Draft
(Click image for 600dpi version…)

After finishing up the work I had to do today I began working on v2.0 of the RS232 to Eaton Leonard Level Shifter. After delivering the first batch the customer wanted some slight changes, most notably a configurable board which could either talk to itself or either end of the communications system the Eaton Leonard benders use. So, after poking with the breadboard on Friday and documenting my findings on Saturday I set to work drawing the board. It’s the same dimensions and the power and data connectors are in the same place, but everything else is different.

I had initially tried to use a resistor network to make soldering easier, but that was going to make connecting everything in such a small space very difficult, so I went back to discreet resistors.

I might change the LEDs and the resistors connected to them. (This will be determined tomorrow.) There also might be a product name change, part number change, and some of the labeling is still up in the air. Other than that, I’m pretty happy with it. Hopefully I’ll order the first run of boards by the end of the week.

I still have to finish working on the photos from the Selfridge airshow this weekend and upload them. That’ll be another night, I think.