1992 Custom Ecu LOOK!

[phantomrt]

On all of the IC chips I worked with in college, the most important pins began at Pin 1. If you place the half-moon shape provision on the end of the chip at the 12 o'clock position, the pin to the left would be pin 1.

So, it makes perfect sense that the pins on the left (in my picture above) would be the unused ones.

[Acidreian]

Quote:

Originally Posted by phantomrt On all of the IC chips I worked with in college, the most important pins began at Pin 1. If you place the half-moon shape provision on the end of the chip at the 12 o'clock position, the pin to the left would be pin 1. So, it makes perfect sense that the pins on the left (in my picture above) would be the unused ones.

makes perfect sense but i did read in some threat it stops some of the gauges from worked after the degrade to a 28pin but ill give it a try thing thing i wanna know now is in a 2.5 cal chip thats different from stock is that interchangeable

[phantomrt]

Unlikely. I say bad information. The ONLY gauge that could quit working would be the tachometer. Coolant temp runs straight from the single wire sensor to the gauge. Battery voltage, oil pressure, and fuel does the same. Tachometer and MAYBE Vehicle speed are the only ones that could be affected.

A SBEC I can be plugged in place of an SBECII and start and run the engine. I proved that. But some of the pinouts are different--one being the ASD relay circuit. Cruise control pinouts are different as is the communication with the BCM.

One thing to note with this setup is that when you switch the engine off, it keeps running for about half a second.

[Shel-Game]

Quote:

Originally Posted by Acidreian i know les then 2% were turbo 2.5's in 1992 what part number u want off the eprom chip or the plastic cover? that sbec II ecu you have has a socket done to it zend me pictures detailed because mine its 32 pin and u say urs has the ablity to socket a 28 i need to know what pins where unused

The 4 pins to the right lower corner of the SBEC are the re-flash control pins. If you swap in an 87C257, you don't use those pins.

Alternately, I make an adapter board so that you can use a 27C256, 27SF512 (more mainstream chips) or even an Ostrich.

[Shel-Game]

Quote:

Originally Posted by Acidreian makes perfect sense but i did read in some threat it stops some of the gauges from worked after the degrade to a 28pin but ill give it a try thing thing i wanna know now is in a 2.5 cal chip thats different from stock is that interchangeable

No, none of the guages or input go directly to that chip. Think of that chip as a hard drive. Would you plug your monitor directly into the hard drive? No, it has to go thru the CPU first. All of those pins are just used to send data back and forth between the memory and CPU. If you miss a pin, the CPU simply will not be able to access the memory.

The 4 pins you don't use are simply the control pins used to reflash the flash chip.

[phantomrt]

This will be the first one I will miss in many many years. Feel free to stop by my house and use my garden hose if anyone wishes to wash cars.

[smithf20]

Does anybody know where you can get the chrysler adapter and software to flash the chips. anybody?

[Shel-Game]

The adapter - eBay. The software, good luck...

[phantomrt]

Quote:

Originally Posted by phantomrt This will be the first one I will miss in many many years. Feel free to stop by my house and use my garden hose if anyone wishes to wash cars.

WTF. This was supposed to go to another thread. Not sure how it happened. Sorry for the confusion.

[MNmopar]

Quote:

Originally Posted by Una The 4 unused holes will be the farthest inboard holes, farthest from the edge of the board.

[QUOTE=Shellgame;2257641]The 4 pins to the right lower corner of the SBEC are the re-flash control pins. If you swap in an 87C257, you don't use those pins.
QUOTE]

The way I'm looking at the board, these comments seem to contradict each other, don't they? Which one is correct?

I'm looking to socket my '92 rt sbec in the next day or so and came across this after being confused about the mis-matching number of pins...

When looking at the "top" of the board (the side that the harness plug plugs into), there are two heat sinks under the main plug, then the chip is to the lower right of that in the corner. When re-socketing this thing, do you ignore the 4 pins closest to the heat sinks (seemingly what una said), or the 4 pins closest to the corner of the board (shellgames suggestion)?

[phantomrt]

My guess would be the ones closest to the heat sink. Pin #1 is on the end of the chip with the half moon thing. Often on IC chips, that is where power is fed to it. I am not sure about these, but usually things start at pin 1.

[MNmopar]

Anyone know?

I know it's Christmas day, just hoping to catch some eyes here...

[ohnotagain]

align pin #1 of the socket with pin #1 of the chip.
almost all chips use pin #1 for main power input.

when looking at the chip with the half moon divit facing straight up pin #1 is the top left pin on the chip.

[phantomrt]

That's exactly how I learned it in my electronics classes. If you don't use the socket's PIN 1, nothing is going to work, because that supplies power to most chips.

[Shel-Game]

NO, what I originally posted was correct. You don't use the 4 right-most pins. (What I posted to you on the other page was wrong, and I corrected myself later). The SBECII can use 3 different kinds of chips - 87C257, the Toshiba chip, and a development module similar to an Ostrich. The power pin is duplicated, and pin 1 is either for programming or used for A15 (on the Toshiba chip). My flash module uses the 'other' 4 pins as a control bus for reflashing. A15 is also duplicated on those pads.

So, the chip in an SBEC or SBECII is always -ALWAYS- as far to the left as possible.