Megajolt LCD display

Discussion on Future Megajolt hardware / software upgrades.

Moderators: JeffC, rdoherty, stieg, brentp

Tadhg
Posts: 9
Joined: Wed Aug 15, 2012 2:38 pm
Location: SE Queensland, Oz

Post by Tadhg »

That all sounds pretty cool Spockie. I've got a Mini (Aussie delivered, so definitely pre-96/OBD/OBD II - didn't notice I hadn't listed my location before) with a kit half installed (trigger wheel and hall effect sensor installed, no electrics installed/connected yet - car's' still running a dissy), and a dash that's been in the build process for nigh on two years. It's been on the road that whole time, of course. So if I could get tacho/temp off the MJ, it'd be extra motivation to install it.

That said, all my mobile devices are iOS based. No problem with Andriod, happy to concede it's a great system. Still looking forward to see what you're producing.

brentp
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Post by brentp »

Keep up the great work! would love to compare notes with what you learned with the ELM chip.

We are going to integrate CAN with RaceCapture/Pro and RaceCapture/Track - this will capture all 2006+ vehicles with one chip/protocol- this will be a good start.
Brent Picasso
CEO and Founder, Autosport Labs
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capri_turbo
Posts: 122
Joined: Tue Jan 10, 2006 8:17 pm
Location: North Yorkshire, UK

Post by capri_turbo »

Just found this thread and realised just how old it is. I have completed a project based on the nixi tube Arduino project and have it up and running off my V3 jolt...

The 9 pin serial port had previously been modified to have the TTL level lines output on pins 7 and 8 and 5V on pin 1 for a bluetooth module that worked quite well...

This powers the arduino and display quite happily.. photo shows it attached to a V3 jolt on the bench hence 0 RPM

I have included an image of the display layout which shows the word "fan" after the temp to show that the fan is running (run off user out 1 hence U/Out 1 being listed too).

The other U/out's show their number instead of the _ when they are "on"
Attachments
display-mounted.jpg
display-mounted.jpg (46.12 KiB) Viewed 58190 times
TTL and power out at d type... must now only use a 3 wire cable (Rx Tx Gnd) for RS232 to a PC etc...
TTL and power out at d type... must now only use a 3 wire cable (Rx Tx Gnd) for RS232 to a PC etc...
Power-TTL-Mods.jpg (43.49 KiB) Viewed 58191 times
Talking to and relaying data from the jolt
Talking to and relaying data from the jolt
display_working_212.jpg (106.7 KiB) Viewed 58191 times

capri_turbo
Posts: 122
Joined: Tue Jan 10, 2006 8:17 pm
Location: North Yorkshire, UK

Post by capri_turbo »

And the display layout image
Attachments
Display layout showing everything "on"... U/outs go to _ when they're off and "fan" disappears when it's off (U/out 1)
Display layout showing everything "on"... U/outs go to _ when they're off and "fan" disappears when it's off (U/out 1)
display-layout.jpg (76.26 KiB) Viewed 58189 times

brentp
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Post by brentp »

Super awesome!
Brent Picasso
CEO and Founder, Autosport Labs
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capri_turbo
Posts: 122
Joined: Tue Jan 10, 2006 8:17 pm
Location: North Yorkshire, UK

Re: Megajolt LCD display

Post by capri_turbo »

Thanks Brent, i'm more than happy to share this project and source code on here.

Not used the Capri on the road this year, but running it to warm on the driveway is showing that the display is working very well.

capri_turbo
Posts: 122
Joined: Tue Jan 10, 2006 8:17 pm
Location: North Yorkshire, UK

Re: Megajolt LCD display

Post by capri_turbo »

Can't believe that a year has passed since I built this:
Display.png
Display.png (252.82 KiB) Viewed 56435 times
Just built an arduino based crank simulator which seems to work quite well... only does 5 fixed points for RPM, but that's enough to bench test the display for now.

Working on an LED display now with an off the shelf display board from Mottram Labs in the UK... it gives a 4 digit readout of RPM with a bargraph too. Just about got it all working and now getting the code written up to use the 4 individual LED's above the 7 segmnets to display the user out status... should have that working tonight.
PIX191001.jpg
PIX191001.jpg (39.95 KiB) Viewed 56435 times
Getting ideas of a full digital dash now... although my wife thinks it's a little too "Knight Rider"... well, it is a 1980's car so why not...

thegecko
Posts: 4
Joined: Tue Feb 27, 2024 8:18 pm

Re: Megajolt LCD display with USB?

Post by thegecko »

Hello,

I have a new MJ with the USB interface. I really want to create a display as others have done here. Has anyone figured out how to get the data out of the USB connector. It seems a usb host capable device would be required then the ability to break out the data. This is the closest project I have found so far. https://hackaday.io/project/177080-remo ... connection

Is it possible to grab the serial data off the MJ board prior to it going the USB? If so - I could copy much of the great work shown here.

Thanks for any ideas!

Pete

thegecko
Posts: 4
Joined: Tue Feb 27, 2024 8:18 pm

Re: Megajolt LCD display

Post by thegecko »

Hi,

Just wanted to let folks I got a USB connected display working with a Raspberry Pi Zero 2W and a 20x4 LCD display, maybe $20 in parts. This is my first ever Pi/python project, so I'm sure my code is ugly, but it works. Takes about 15 seconds to boot up - will work to make that faster.

It's got
- Ignition map toggle indicator
- Advance
- Manifold Pressure
- RPM
- Advance Correction based on potentiometer input

If you have questions, let me know.

Image

brentp
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Re: Megajolt LCD display

Post by brentp »

Well done on what is obviously a fun project! Please keep posting updates - and share a video if you can! :)
Brent Picasso
CEO and Founder, Autosport Labs
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thegecko
Posts: 4
Joined: Tue Feb 27, 2024 8:18 pm

Re: Megajolt LCD display

Post by thegecko »

Hello,

Made a quick video of the Raspberry Pi based Megajolt display. It's running test data in the video, but works well on the test bench, too. It runs a RPi Zero 2W($15) and a 128x32 OLED display ($3). Lots of fun discovering how Python works and how to hook it all up. Hope to have it flying in the experimental aircraft soon.

https://www.youtube.com/watch?v=RFH1ge5eoFk

Image

thegecko
Posts: 4
Joined: Tue Feb 27, 2024 8:18 pm

Re: Megajolt LCD display

Post by thegecko »

The MJ is installed and running in the experimental plane. Working great! Photo below is the sightseeing cruise setting at over 100kts TAS and 3.5 GPH. (Way more efficient than a factory plane1) Economy cruise is 150KTAS on 6GPH. Both using cheap car gas.

The effective advance is less than 38 deg b/c the other ignition is fixed at 23 BTDC. I'm very happy with the results!

The display is showing Take off or Cruise timing curve(CR)||Current advance (38)||advance correction via the knob.(+2)

Image

brentp
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Re: Megajolt LCD display

Post by brentp »

Cool project! Well done!

As usual, we strongly discourage using Megajolt in an airplane, as it is not rated for such use.

-Brent
Brent Picasso
CEO and Founder, Autosport Labs
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