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1984-1989 1.5 DIN Car Computer project

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Old 04-28-2018, 11:18 AM
  #61  
Keith Huffstutler
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The video quality isn't good enough to see that when I press the over-drive button on my shifter, one of the bits changes from a 0 to a 1.
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
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Old 05-02-2018, 03:09 PM
  #62  
LWesthaver
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Originally Posted by Keith Huffstutler View Post
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
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:
Code:
 PROMIDA   PROMIDB
000011110 010101011
 |      |  |      |
 +-1Eh--+  +-ABh--+
 |                |
 +-----7851d------+
My car has a PROMID of 1EAB Hex or 7851 Decimal.
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Old 07-09-2018, 10:13 AM
  #63  
-=Jeff=-
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I was curious if you would be willing to share your Arduino code. I would like to try it out..

Thanks
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Old 07-09-2018, 03:36 PM
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LWesthaver
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Originally Posted by -=Jeff=- View Post
I was curious if you would be willing to share your Arduino code. I would like to try it out..

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

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

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Old 07-10-2018, 01:23 AM
  #65  
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Originally Posted by LWesthaver View Post
Sure, here's a link: Arduino 160 Baud ALDL Reader

The download link for the Arduino code is near the bottom of the page.
Nicely commented, thanks!
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Old 07-12-2018, 09:20 AM
  #66  
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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
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Old 07-12-2018, 05:30 PM
  #67  
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Originally Posted by -=Jeff=- View Post
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
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.

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Old 07-12-2018, 10:37 PM
  #68  
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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.
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