Here's what I found in the DIY-EFI FTP site regarding the 16 pin chip on the memcal. Has anyone confirmed this and does anyone know what the possible pinouts are for the 14-pin? or is that even a netres?

I'm only asking because I *may* consider making a whole new memcal to be able to fit a larger chip, if i can't *make* the netres, then possilby moving them around as long as the pins go to the corresponding pin in the ECM ... kinda squeeze them off to the right side to fit a 32 pin chip and a ZIF ... neat project, but I figure if I take long enough time to plan and do this (whether or not I have to have the board professionally done or not) at least it will be done once and done right.

THE FOLLOWING IMAGE IS NOT FOR 305/350 TPI 86-88 may be for another application i have yet to figure out ... 165 was used in more than just TPI's right?

 

I just checked with the ohmmeter ... the only pins that are correct on this diagram are the bottom ones ... going from 1 to 2 I get about 160K so that circuit diagram is crap.

...

 

Here's teh deal that I'm thinking of. You get the resistance right between all pins, just like the chip, no matter how you have it configured, your car should still run (granted the eprom is pulled).

I'm going to spend a few hours and see if I can't come up with a resister network of my own! (why am I doing this?) To build a complete memcal from scratch. Why? Don't ask. I just like this ****. But wouldn't it be a contribution that I built a resistor network from scratch, tested it, worked and let the world see? That's what I think our hobby should consist of is people willing to put a little extra work for everyone else to see and for free.

Of course, it would be nice if someone who had the exact figures for the chips, let us know, eh?

 

Yeah, map that bugger out! I guess it'll be different for different setups, right? 350 or 305?

If you wanna try a DIY switcher, I can send you a couple PCBs that are mapped to a 32-pin, but it's setup for putting the Memcal/netres on its side.

Nothing says you can't be set up to take the Netres right onto a PCB though... That'd be pretty sweet.

As for the 730's...

 

As for the 730's ... you're on your own! LOL! ...

Well, you asked for it. It took a little while and I have yet to test this out ... I don't think I have enough variation of resistors on hand, that's another thing ...

But anyway, there are a couple of ones i'm not sure of the value (marked w/ ?) but if anyone has a memcal for the 165 ECM for 86 to 88 TPI (305 or 350)- is the same part # between the two, I have an 86 305 TPI memcal and an 88 350 TPI and the chips are the same.

This one is the 16-pin one. haven't had time to do the 14. if you measure out the pins, you may be pleasantly surprised. I'll be on vacation until Tues so have fun!

 

Oh yeah, Craig, I wouldn't mind a couple o pcbs to work with if you don't mind. e-mail me at areinike@iroczone.com. remember, i'll be out until Tues so i'll chat with ya then!

Take care! (anything to help the hobby!)

 

Hey Allan; I wish i had your electrical passion as i'm just starting on the eeprom switch. I agree with the notion of "buggering" with it to show the world (for free). It is a higher level of moral reasoning that one does such a thing. This is what makes the car enthusiast....especially F-body so appealing. Nurturing passion and creativity in our kids is a base for bettering mankind.

Keep sharing....

Stan:lala:

 

Just an update. snagged me an uber variety resistor pack. I'm going to use my breadboard and see if I can match resistance and test out my theory.

If all goes well, I can just plug in the resistor packs minus the EPROM and the engine will still run right? just in limp mode ... also give me a PROM code, but just testing ...

 

Hey Craig, just wondering if you tried e-mailing me. I have had problems with that e-mail account and didn't know if you had e-mailed me or not. Anywho .. I have a 29C010, 29C020 and even a 29C040 I snagged as samples. I also managed to get SST to send me 3 of thier 27SF512 chips. Don't know if they'll work, but I didn't pay for them

Still trying to find the time to map out the 14 pin chip and test with my protoboard, the 16-pin deal. I think I have a vast amount of resistors to work with (that 500 pack deally from RatShack).

Until next time!

Keep burnin!

 

Made more progress on the NetRes mapping? I got my hands on a couple of 165's with non-TPI Memcals in em, so now I'm motivated...

 

I should be able to get around to it next week. Wife works and I'm off ... hehehe ...

 

I went through a Memcal with the meter this AM, and came up with a couple of tables for resistance between numerous pins. The Excel spreadsheet is attached. I haven't tried to reduce it to a resistor network equivalent circuit, but it seems like there's a lot of commonalities and additives, so it should be possible.

-Craig

 

Good start. I started to do that with the 14 pin, but since reorganized my garage to make way for the engine rebuild - I don't know where it's at, BUT, i'll be using your chart for sure - good job!

 

Okay, Craig ... apparently, there is a difference between the TPI and non-TPI resnets .. attached is what I have - compare to yours and you'll see quite a bit of difference in measurements and schematic if you think about it.

Interesting stuff, huh ...

 

If you look closely, there is some sort of pattern in the readings. Take this for example. On the spreadsheet, look at the DIFFERENCE between the values from pins 14 - 1 and 14 -2 ... all the way across. 13-1 to 13-2, 12-1 to 12-2, etc. At least on my readings, they were all about 2.2K difference down the line. Craig, your readings are about 5.8K different down the line.

That may help in mapping this bugger out, but this 14-pin chip is going to take some time to map out. And I'm not sure how feasible it is to use standard resistors to make this happen. Which is why I brought up the differences in values above - perhaps building a circuit with some adjustable pots would work if mapped out correctly .... what we need is an engineer who designed these laser etched resistor networks to just tell us!! .

 

That would be very nice to have a setup whereby you could just 'dial' in for different variants. That's my hope. Part of why I posted the 'different' Memcal numbers, hoping that by analyzing the differences some generalized approach can be had.

It'd be real great if you could just take a 6-banger ResNet and solder on an extra resistor or something. Better yet if you could either have a couple pots or swap-outs for different combos. Seems like for the moment, making something which works for TPI V8s is a primary target. And then...

 

just a thought folks. texas instrument built these chips why not drop them an email and see if they have any old ones around. ive seen ADS memcal that have the correct chips so its pretty obvious that somebody got the part numbers and ordered a few. if they are avaiable lets do a group buy and get it together.