What does it mean when you stack BIN's on a larger chip? What is the advantage or purpose?

 

On the earlier codes-165 maf; the proms are "27C128" and the later map's are "256", having twice the area on them and more code. The 128s have a window in them and must be erased with uv light in an eraser. This takes anywhere from 10 minutes and increases the more times you erase and reprogram them, and eventually they won't fully erase and take a reprogram.
With the 256s they are available as eeproms-they can just be reprogrammed over-no window; no uv erase. Real fast and they never wear out.
Now if you use a 256 in a 128 application; the address's that the ecm looks for are not where they should be. But if you "double the bin", then that places one bin where it "belongs" as far as address's. Or you can just change the start of device to 04000; but then you must read that 256 as a 128 with the pocket programmer to see it correctly.
Also, I believe it's Craig Moates?, has gone even further....working on a prom adaptor with a switch-(using larger proms for a given application)-so you could potentially load 4 bins on a single prom; then just flip the switch to change amongst the 4 bins; each with a bit different program.....Anyone heard how that projects going? :cool:


[Modified by drive it, 12:18 AM 4/11/2003]

 

I can use my own 1984 Corvette as example.

It has an 1k chip in the ECM.

As you see it has 10 address pins ( A0 to A9 ). With each address pin you can double the size of the eprom 2*2*2*2*2*2*2*2*2*2=1024=1k

I installed another 4k chip.

Note that this chip has two additional address pins. ( A10 and A11 )
This chip size is 1024*2*2=4096=4k. By grounding these two extra address pins it will work just like the stock 1k prom if I program the first 1k with my 1k bin file from the stock chip. By putting 5v pn A10 the ECM will read from the second 1k instead. By using pull up resistors to the two additional address pins, and grouding switches it is easy to select which 1k area in the 4k prom the ECM will use. I can prepare four different calibrations and burn them one after another in the chip. By flipping the switches I select which one to use.

on on - 1st one
off on - 2nd one
on off - 3rd one
off off - 4th one

You can use as lage eprom as you like of you build an adapter to the stock ECM chip socket and add switches for the extra address pins.

This is Craig Moates page on the subject: http://moates.net/docs/switchin.html




[Modified by JoBy, 2:13 PM 4/11/2003]

 

WOW!!!!! Those are probably the two most straight forward and informative answers I've ever gotten. I have experience in Electronics, but I didn't really put it together until now. I have been to Craig's site. That is where these questions originated. I see alot of software on that site, but I didn't see clear explanations of what they were for. VEPHD is one. I assume from the name that it is some sort of Volumetric Efficiency fix. Is there more info on that page that I missed, or am I just stupid? Ok don't answer the last ?. Thanks