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cout
01-04-2011, 11:25 PM
I have written a new library for communicating to my SMEC via DRBII:

http://github.com/cout/drbii
http://github.com/cout/ftdic

It runs on linux and is written in ruby. I have written a simple tachometer program in opengl which I'm hoping will serve as the basis for a DIY HUD.

I have combed through the turbonator source code and have implemented the DRBII protocol to the best of my ability without being able to plug in.

Problem is, when I do plug in, before I send anything, I get a never-ending a stream of null bytes (at one point I did send a byte, and the computer just echoed it back to me over and over).

I have connected the orange (TX?) wire on the FTDI cable to the green (RX?) wire on the SCI. I have also connected the yellow (RX?) wire on the FTDI cable to the pink (TX?) wire on the SCI. Since I am using SCI, I have enabled bitbang mode in libftdi.

1. Is this behavior (constant stream of bytes) expected?

2. What baud rate should I be using? I've tried both 7812 and 976. I'm not (yet) sending the command to enter high-speed mode.

3. How do I know if my cal has the high-speed logger enabled? Not sure if this will help, but here's a pic of the IC:

http://farm6.static.flickr.com/5285/5325335351_08487cc06c_z.jpg (http://www.flickr.com/photos/curlypaul/5325335351/)

It is a cal from shelgame, but at the moment that's all I know.

tsiconquest88
01-04-2011, 11:37 PM
Ohhhh i read your email and responded. BUT i ad no idea you were actually trying to change things with the cal. I have no idea how to do that!!! But yea Rob should be able to help you. What have you done with the van so far?
OH also, to add to my email, another thing the chip has was no overboost- which is the NO OB. Meaning the stock 14.7 cut-off is no longer there. Can boost to what you want per accomodating mods that is lol. The chip is also cal'd for 15 or so psi.

cout
01-05-2011, 12:41 AM
Thanks Joe!

So far I've mostly just been working on the electrical gremlins. I fixed the short circuit a while back but the wiring was still a mess and at first I put it back together wrong (with the alternator directly charging the battery instead of going to the junction). I've been learning how to solder and the wiring is almost completely cleaned up (with fusible links instead of fuses, unfortunately). I also added a tow hitch so I can put our spare LeMons engine on a trailer instead of keeping it in the back of the van. I've got a worklog thread but at the moment it's a little behind.

No overboost is good news, so long as I'm dialed down. I'm at 9psi at the moment but I haven't tried adjusting boost at all yet. I want to switch to a wideband O2 first so I don't blow anything up. I also don't trust the boost gauge anymore since I accidentally melted the casing when I installed the wrong kind of bulb. :banghead:

What's the best way these days to add more fuel above 14psi?

I'm not trying to change the cal (yet), just datalogging at the moment. I think I figured my problem out not long after I posted the question (I was using normal bitbang mode instead of synchronous bitbang, silly me). There are still a few bugs left to work out but I hope to post a screenshot soon of the tachometer in action!

tsiconquest88
01-05-2011, 08:15 AM
The cal it has already lets you run up to 15 psi is what i meant. With the stock turbo that is. It has the overboost disabled and fuel/spark cal'd for 15 psi or so. You have the walbro there to support what you want as well, just throw some bigger injectors, the WB for knowing real AF readings. And adjustable reg after the stocker or in place of the stocker would be ok too. Not sure where your looking to go with the power level.
Oh and again sorry i left wiring the way it was, i was frustrated and figured why put it back in case the issue was somewhere there, it wouldnt have to be un-done again by the buyer. Which i already said so yea lol. To put it back really shouldnt of been that big a deal though. But trying to explain without being in person is touch on both of us lol. And since you hadnt ever seen how the wiring was in the first place on a turbo mini made it tougher on you im sure.

ShelGame
01-05-2011, 09:00 AM
I have written a new library for communicating to my SMEC via DRBII:

http://github.com/cout/drbii
http://github.com/cout/ftdic

It runs on linux and is written in ruby. I have written a simple tachometer program in opengl which I'm hoping will serve as the basis for a DIY HUD.

I have combed through the turbonator source code and have implemented the DRBII protocol to the best of my ability without being able to plug in.

Problem is, when I do plug in, before I send anything, I get a never-ending a stream of null bytes (at one point I did send a byte, and the computer just echoed it back to me over and over).

I have connected the orange (TX?) wire on the FTDI cable to the green (RX?) wire on the SCI. I have also connected the yellow (RX?) wire on the FTDI cable to the pink (TX?) wire on the SCI. Since I am using SCI, I have enabled bitbang mode in libftdi.

1. Is this behavior (constant stream of bytes) expected?

2. What baud rate should I be using? I've tried both 7812 and 976. I'm not (yet) sending the command to enter high-speed mode.

3. How do I know if my cal has the high-speed logger enabled? Not sure if this will help, but here's a pic of the IC:

http://farm6.static.flickr.com/5285/5325335351_08487cc06c_z.jpg (http://www.flickr.com/photos/curlypaul/5325335351/)

It is a cal from shelgame, but at the moment that's all I know.

Have you inverted the logic levels at the SMEC side? On the SMEC, a logic 'high' is 0v, and logic 'low' is 5V. Not sure why Chrysler did that other than to make it hard to communicate. But, if you are not using inverted logic on the FTDI chip, it might interpret the 5v static line from the SMEC as a string of 0xFF's.

The T1 SMEC used the DRBII protocol. Which should have baud rates of 7812 and 62500.

That chip I made for Joe doesn't have the high-speed logger mod enabled. I don't think I've added that mod to any customer cals ever.

tsiconquest88
01-05-2011, 11:47 AM
Thanks for giving him the info Rob.