ALDL LCD Display

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
BennVenn
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Re: ALDL LCD Display

Post by BennVenn »

you would add something like this to the CONDITIONS{} area in the config file

IO1=VAR09>0BB8=00;
IO1=VAR09<0AF0=FF;

This is assuming RPM is assigned to VAR09 (in the math section)

IO1 output is set to 00 (0% duty cycle, or effectively off) when VAR09 (the RPM) is > (greater than) hex value 0BB8 (in decimal = 3000RPM)
it'll then check the next condition
IO1 output is set to FF (100% duty cycle, or ON) when VAR09 (the RPM) is < (less than) hex value 0AF0 (in decimal = 2800RPM)

so assuming you had IO1 going to a relay which is powering the ignition coil, if you go over 3000RPM it'll shut the relay off until RPM falls below 2800RPM.

You can also add more conditions after it, example

IO1=VAR02>00C8=00;

here, IO1 is turned off (0% duty) when VAR02 > 200KPA. Like a boost safety.

Every packet that is received from the ECU, all the conditions are checked once again, so it is the last valid condition that actually controls the IO.

This would always give you 2step which is probably not ideal. You could disable it with a rocker switch or push button, or I can update the code so you can assign a VAR with IO2's logic state. So you could check for a pushbutton press in the conditions, from IO2, and have that enable or disable the 2 step.

Sorry if this reads as a little complicated! Might be best to connect a test lamp / led to the IO1 output and try some code to see how it works, and if you need the IO2 as an input into a VARxx, I'll code that up
BennVenn
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Location: Windellama, NSW

Re: ALDL LCD Display

Post by BennVenn »

Shutting the coil off, especially if it has already began charging in a dwell cycle, will result in an early spark which may not be ideal at 3500rpm and 9psi of boost... If you can use 12p's mapB for this instead that might be better. You could add a small circuit to only shut off the coil after the falling edge of the EST signal, that'll guarantee no early spark but its not something the lcd can do in its current firmware
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Vrv8hz
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Re: ALDL LCD Display

Post by Vrv8hz »

The steering wheel blocks out the temp gauge location, but there was a space in the middle not being used.
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antus
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Re: ALDL LCD Display

Post by antus »

That looks way cool. Wish I could have done that back when I had a VL. Or the other VL.
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Vrv8hz
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Re: ALDL LCD Display

Post by Vrv8hz »

antus wrote: Sun Nov 24, 2024 10:19 am That looks way cool. Wish I could have done that back when I had a VL. Or the other VL.
Can't have too many VLs
BennVenn
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Re: ALDL LCD Display

Post by BennVenn »

Looking good!! Is the SD card accessible?

Looks like your MAP math is a little off

//1Bar ((X * 0.369) + 10.354) --
;MAP
VARIABLE=02
BITS=8
RXPOS=28
MUL=00000171
OFFSET=00002872
DIVISOR=000003E8

//2Bar ((X * 0.781) + 8)
;MAP
VARIABLE=02
BITS=8
RXPOS=28
MUL=0000030D
OFFSET=00001F40
DIVISOR=000003E8
Last edited by BennVenn on Sun Nov 24, 2024 9:35 pm, edited 1 time in total.
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Vrv8hz
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Re: ALDL LCD Display

Post by Vrv8hz »

No it is not at all accessible, but I have ordered a tf extension cable to make changes a bit easier in the future. Yeah I was thinking that it was going really well for 140kpa 😆
BennVenn
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Re: ALDL LCD Display

Post by BennVenn »

Do you think the option for updating the config over usbcomms could be useful?
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Vrv8hz
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Re: ALDL LCD Display

Post by Vrv8hz »

Yes, but wouldn't the config need to be changed to passive to do that?
BennVenn
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cars: R33 GTST, '60 Vw Bug, Express (4G63T), GW X200
Location: Windellama, NSW

Re: ALDL LCD Display

Post by BennVenn »

It would be a firmware update, checks for a specific header from the PC which the ECU wouldn't be able to generate and then transfers the data to the Config file.