Well let's start working on some updates! Life has intervened a bit the last 2 months so some progress has been slower than hoped for. On the other hand progress is being made on updates and improvements I am already figuring out from having got this board this far. Updates are a little hard to write now because I am working on many fronts and am not sure where to begin or how to organize writing about what I am doing.
I suppose like many of our builds it can start with a picture of the build table.
And here it is. In those boxes are the parts that have been ordered to put on the circuit boards. I took one of the parts reels out to show you. These reels are placed in a robot which will put them on the board accurately with solder in a paste form and then the boards are run thru an oven. The reel in the picture is 7" in diameter and is holding 5000 resistors. It turns out these particular resistors have no resistance, which I find sort of humorous.
Those boxes have everything needed for the automated assembly and it looks like the files for the robot to do placement are correct. There were 3 incorrect footprints for caps, but I think they will work or I will hand put in the alternates. Speaking of which I will also be getting a proper soldering setup for these boards along with a 14 MP USB microscope to see what I am doing. The soldering station has very accurate temperature control and heated tweezers so you can add / remove the little parts easily.
All of these parts are automotive rated which applies extended temperature service and also a great deal more testing of parts during production with lot control etc. to produce more reliable parts. They also cost more for the same part, sometimes 2 or 3 times as much. The modern ECU is not expensive to build though and there is no need to cut any corners. Si I am trying to buy the best parts available.
All OEM ECU's are built to high standards. I think the units we use are subject to more handling and potential wiring mishaps etc. so I think building in some additional protection is a sensible thing. The prototype boards have additional protection above what you probably find on an OEM ECU. For example sensor inputs with voltage clamps which react in 1/4 of one billionth of a second when hit with a static charge. If I remember, they cost a whole 9 cents per channel.
I'm willing to go into depth on almost anything about this and actually have a lot more to say about what I've learned the last year doing this project. Probably the best things to try to cover next would be some practical stuff about our little 302 buddies, wiring for these and what ever else you guys want.