Keith Huffstutler

Looked crisp and clear for me (takes like 10 seconds to clear up, for some reason). Third column, 4th row to the bottom, 2nd to the last digit.

Nice job!

Keith

LWesthaver

I forgot that I could go full-screen with the video! Once it's larger, you can see the particular bit that's getting flipped:



If you're into binary, you can also see the PROMID's in the top row, 3rd and 4th bytes (fyi: the ECM always sends a start bit (0) followed by 8 data bits so the leading zero is not part of the data). These values indicate the version of the Programmable Read Only Memory chip installed in the car:


My car has a PROMID of 1EAB Hex or 7851 Decimal.

-=Jeff=-

I was curious if you would be willing to share your Arduino code. I would like to try it out..

Thanks

LWesthaver

Sure, here's a link: Arduino 160 Baud ALDL Reader

The download link for the Arduino code is near the bottom of the page.

knikula

Nicely commented, thanks!

-=Jeff=-

Have you started to look at the 8912 stuff at all? wondering if the protocol design is the same, but adjusted for the faster data rate

LWesthaver

The 8192 protocol is quite a bit different. It is a request/response protocol. It doesn't just stream endlessly once initiated like the 160 protocol. And there are more timing issues to deal with. But it is a faster/better protocol. I've found some helpful people who have provided some guidance and I hope to start coding for the 8192 protocol soon. But I've got a few other tasks I need to complete first.

scorp508

This is an absolutely amazing project, congrats on everything you have done thus far! I was looking at my 1.5 DIN aftermarket Pioneer unit earlier today thinking "Why do these all look so terrible?" then stumbled upon this thread. Amazing work, really, it's rare anyone goes to these lengths to help our early C4s.

Z51BOB

I looked at this thread in amazement a few months ago. This combination looks like a perfect way to replace the junk aftermarket radio in my '85 and provide a platform for the 10 - 18 hz GPS datalogger I want to build for Autocross. Over the past 3 years I've spent a lot of time inside the $6E code for the 1227165 ecm I installed in my car, including successfully modifying and reassembling the source code from the disassembly hack. My initial vision is to use an ESP32 (programmed in Arduino IDE) to log both the GPS and ALDL Datastream then hand a combined stream to the Raspberry PI for display and long term storage. If there's interest I can post what I come up with here. I Hope to save some time for LWesthaver to use on the main part of his build.

LWesthaver

I would be very interested in anything you have learned about modifying the ECM code. To me that's kinda the last frontier.

I can tell you that a cheap USB GPS puck plugged into the raspberry pi works great. I wouldn't use an Arduino for that task as it isn't time-critical. But the ECM data stream which is time-critical needs to be handled by a dedicated processor like the Arduino.

What led you to choose the ESP32? It's new to me so I just looked it up. Would it be a better choice than a garden variety Arduino?

If you would like to discuss the low level details of what I've been doing, send me a PM. I'd like to hear more about what you are doing.

--Wes

Z51BOB

I've started using ESP32's and ESP8266 instead of Arduinos because they are about 20x faster, have 1MB program space and have built in WiFi for around $6 each and can be ultra low power. They work well with the Arduino development environment. I'll send you a PM.

Z51BOB

LWesthaver

In my experience 3D printing is great for creating basic shapes to validate a design but the finish quality is really poor. Most 3D printed objects have a very rough texture. Not the kind of finish most people would consider production quality.

In some of my past projects, I've contracted with a local company that makes overlays (just like the overlay on the original BOSE head unit). I am considering going in that direction for this project. The overlay could use the same font and font size as the original BOSE overlay and have translucent lettering that is backlit like the BOSE overlay. I think that would come the closest to duplicating the look of the OEM radio. The down side is that you have to purchase the overlays in quantity in order to drive the price down. So the design has to be set in stone before you commit to producing them.

Z51BOB

I really would like to build one of these. I have already ordered Pi3 and LCD.
1) The overlays sound like a good solution for the faceplate. How much are we talking about for a sample quantity including setup, etc?
2) Should have some Arduino compatible code for the 8192 data stream in a few more days.
3) Can you fill us in on the rest of the components for the radio and sound system, brackets, etc?

Steves LS6

Very cool!

LWesthaver

Bob, I apologize for the delay in replying.

To get overlays produced, it is probably going to be about $500. The $500 initial fee usually yields about 10 prototypes. The fab house typically has to prepare silkscreens and cutting dies and the $500 minimum price defrays that cost. That's why I'm hesitant to move in that direction unless this project really blows up. In the meantime, I'll just continue to produce machine-cut faceplate overlays.

How is the Arduino code coming along?

I've been putting together a website to publish all the project info. It's still *very* early in the process but here's the link:

http://www.Comvette.com/

Let me know what you need help with and I'll see if I can assist. If you have any suggestions on how best to present all of my project files and information, please let me know.

Z51BOB

-=Jeff=-

that would be awesome

LWesthaver

Awesome! I'm guessing that you chose the Arduino Mega because it has more than one UART? Did you run into any problems handling spurious noise on the ALDL data line? Aside from needing 2 UARTs (1 input and 1 output) what do you think is the smallest/cheapest micro-controller your code will run on? Just for clarity, when you say the data is running at 10Hz does that mean that you receive 10 complete ALDL data packets per second?

If you've cracked this nut, I'd say that you've opened the door for some really cool and innovative things. As much as I like and appreciate software packages like Tuner Pro, it would be great to see more and different ways of using the ECM ALDL data beyond lugging a laptop computer around.

I considered using GitHub for my project (and still might) but for the sake of not having learn yet another thing, I chose to publish from my own website.

Keep us posted! I can't wait to see what you've done!

-Wes

-=Jeff=-

Z51Bob,

looking forward to seeing what you came up with. What year car? I would love to try it on my 1990, but I know my ALDL stream while the same size is a bit different due to being a ZR-1. Also I am curious how this will work with a CCM Chattering as well