LCD Gauge Update #3: 35 Data Items on 16 Pages!
 

Unfortunately, I didn't keep everything to one thread :(
Here is my attempt to fix this, incase you want to follow from the start

First thread:
Jan 28/2022, DIY Mini-Dash LCD Gauges Update:
http://www.the370z.com/engine-drivet...es-update.html

Second thread:
Feb 16/2022, DIY Mini-Dash LCD Gauges Update #2 - New Layout & Multiple Screens!
http://www.the370z.com/engine-drivet...e-screens.html



I am pleased to report some MORE excellent progress on the mini-dash LCD gauges!

This version shows 35 unique data items (see full list below video link), on 16 different pages, that are meaningful for the 370 enthusiast.
To change the displayed page, just push the cruise on/off button twice within 1.5 seconds. Super easy!
Also, when your headlights turn on and the dash dims, so does the gauge back light. No illumination wiring needed!

Once the snow clears, the next video will show the gauge operation while going for a drive in the country.



Full list of available data items:
Data items from the "Bluetooth Sensor Server" and additional sensors:
• Engine oil pressure
• Fuel pressure
• Manual transmission oil temperature
• Differential oil temperature
• up to 4 additional temperature, pressure or even ethanol sensors.

From the car's network (CAN bus)
• ECT: Engine coolant temperature
• EOT: Engine oil temperature
• EOP: Engine oil pressure
• AFR B1: Air/fuel ratio bank 1
• AFR B2: Air/fuel ratio bank 2
• Individual wheel speed
• MAF 1: Mass air flow, bank 1
• MAF 2: Mass air flow, bank 2
• IAT: Intake air temperature
• MAP: Intake manifold pressure (aka boost sensor)
• TB 1: Throttle body absolute position bank 1
• TB 2: Throttle body absolute position bank 2
• APP: Accelerator pedal position
• IGN: Cylinder #1 ignition timing
• TORQ: Engine torque
• HP: Calculated HP (from engine torque & engine RPM)
• AWD: Front wheel torque. 0% = RWD only, 100% = fully AWD and 50/50 torque split
• SIDE g: Lateral acceleration
• STRG: Steering wheel angle
• TOT: Automatic transmission fluid temp
• IN RPM: Automatic transmission input shaft RPM
• OUT RPM: Automatic transmission output shaft RPM
• GEAR: Automatic transmission current gear (1-7)
• Automatic transmission torque converter status: Locked or Sliding
• BRAKE PSI: Brake line pressure
• BARO: Outside air pressure
• OUT TEMP: Outside air temp
• CRUISE: Cruise control set speed
• RAD FAN: Rad fan duty cycle. 0% = off, 100% = full speed
• VOLTS: System voltage
• CFM: Calculated, real time engine air flow in cubic feet per minute. Uses intake air temperature and outside air pressure to calculate intake manifold air density and uses the total mass air flow to calculate actual engine air flow.

it might be nice to have all this in a single thread.
a thread is like a history of a project. spreading it all over multiple threads isn't so great.

You can always edit the main post of a thread with your updates. :twocents:

aside from that
this project looks amazing. I want one! Excited to see what the final graphics end up looking like. And the enclosure options.

This is really nifty. Not sure if you've checked this out yet, but the raspberry pi 7" touch screen fits very nicely in the cubby hole. If I could find a way to cleanly cover up the holes where the hinges go in and out, this would be a great second screen. My head unit also has HDMI input, so might just utilize that but not sure yet if audio will work while viewing HDMI.

*edit* was trying to figure out why that air vent didn't look right - you have a g37 so the above may be useless info :)

Not at all! The 370z and G37 CAN bus is very similar and I am working to support both.

How long does you pi take to boot up?

It would be pretty cool as a replacement for the 370z left circle display.

You could even make the graphics looks like that old screen.
And since you have the data you could replace the fuel bar and temp bar with higher resolution bars on your screen. Maybe make it easily removable if the user has to access the original lcd for some reason.

http://www.the370z.com/members/z_you...auge-black.jpg

Just cover this right up and put a much more useful display there.
I would definitely buy one.

with a display like this maybe?
https://www.szmaclight.com/product/R...-mipi-RGB.html

that would be the definition of OEM plus. and unobtrusive upgrade.

Thanks for the input. I though about adding it to the existing thread, but was worried it would be deeply buried and not seen by new thread viewers.
The thread views is one of a few factors I use to determine what platform (G, Z or Q) I should focus on. If that is a problem, I have no issue moving the thread.

i think it would be nice to see it progress in a single thread over time. much easier to track the project that way.

Thanks for this suggestion! I really like that idea.

370 gauge clusters are expensive at more than $220 Canadian. I can get a G37 cluster for about $50 at the local scrap yard... I guess that is the "Z tax" :)

To start, I like the idea of something external (that doesn't look like an add-on) that I can use to test/prove the durability of the hardware and software in different operating conditions. If something does fail or act weird, it is an easy replacement.

Once the durability is proven, I will buy a 370 cluster and see how this could work.
If you have any other suggestions, please keep them coming :)

OK.
How do I do that? I didn't see anything under "Thread Tools"

i don't think you need a 370z gauge cluster to test this. Just needs to be the proper diameter circle to fit over the lcd screen. I can measure mine. And since i'm near you if you want to test a fit you can test it on mine. I have some 3d printers here to make a mounting plate maybe if that would help (once i figure out how to use them).

If you covered the entire area of the circle in the cluster you'd have to reimplement the status leds in software (do you have all that data via can?)

or the screen could just cover the inner portion and leave the status leds outer ring visible.

as for the thread thing. there's nothing to do. just post your updates in this thread as new posts. everytime a new post happens the thread rises to the top so it won't get lost.

If you want to update the first post with detail you just click the edit button on it.

usually people will keep the original content of the first post and put their edits either on top or on bottom. you can link to other posts with updates kind of like a table of contents.

also it might be nice to find the other threads you made and add links to them in the first post. so people following this thread know that there are other (buried) thread related to the project.

also i don't think many people view forums by "new thread" it's usually by new posts. at least for daily consumption. that's why there's a new posts button. (that's what i imagine most people use on this forum). so whenever you add a new post your thread will rise to the top for people to read the update. (basically how forums have always worked. I've been following some threads for years and year on this and other forums. splitting it into multiple thread makes things much harder to follow)

I have 3 of these clusters at the house and they sure are expensive. From taking them apart I can't see a passive way to install, almost 90% sure printing it would be the only option.

What I do envision is this going in the center storage (where non navi install their tablets)

This LCD gauge will be a hot item for sure!

When you mentioned this, I was thinking about removing the factory LCD screen and replace it with a LCD screen driven by my hardware. I think that would look great, but would make for a tricky DIY install, depending on the the cluster is assembled.

I will keep this in mind, but for now, I need to stay focused on continued testing of the gauges/hardware on my car. I want to make sure the platform is rock solid so others don't have any issues.

Also, tomorrow I will update the thread like you mentioned. :)

I'd replace my 4 gauges with Frank's screen and install it in the cubby area again

I'd need to know a bit more about the project to be sure it's even feasible, but a pi3 can fastboot in about 2-3 seconds. I guess I assumed based on the form factor that is what you were using here to run the front end display, but I need to go back and read your other posts.

For your gauges, is this correct?
• Boost
• Oil Pressure
• Oil Temp
• Air/Fuel ratio
• Ethanol content

Are they all standalone gauges & sensors?

I am using a $8 ESP-32 micro controller to read the CAN bus, read the Bluetooth data, and drive the LCD display. It is quite the powerhouse!!

Two of the initial design goals was to be affordable and instant start up.

Down the road, I will be looking at using a pi as that will make it easy to drive a larger display. For now, I am focusing on a small (easier to place on the dash) display.

The most difficult and time consuming part of this project has been reverse engineering the CAN bus on multiple Nissan/Infiniti vehicles (like 370, G37, M56, Q50, etc) This is the only way to know if the gauges will work, or what to change in the code so they do work.

Hey BULL, it was nice to chat yesterday.
Thanks for the offer to send me some pics of the disassembled 370 cluster. That will allow me to see inside the cluster without buying one. (for now!)

All correct except water temp instead of oil temp. All standalone

Really enjoying seeing your progress on this project! Just to clarify, engine oil pressure is NOT on the CAN bus, right? Just a low oil pressure switch. Which aftermarket oil pressure sensor are you using that can send data to the bluetooth sensor server?

I'm glad you have been following the progress. It has evolved into much more than I expected when I first started on it just over a year ago.

Correct, engine oil pressure is not on the CAN bus.

I am using a 150 PSI Honeywell PX3 pressure sensor for oil pressure and a 100 PSI PX3 for fuel pressure.

The Bluetooth sensor server will work with any 5v, 3 wire pressure sensor. They typically output 0.5 volts at 0 psi and 4.5 volts at the max rated pressure.
It does the analog to digital conversion, applies the scale and offset, then sends the data out via Bluetooth.

Very familiar with that platform, granted when I was using them they were mostly used for WiFi gpio to control relays and the like, but not much else. Im guessing then you're using i2c for the screen output which wouldn't even require going to a pi as there are plenty of larger i2c screens available and the resolution and refresh rates seem to be adequate. More and more impressed with this project the more I learn about it, thanks for sharing!

I think you meant SPI, not I2C... I2C is too slow for a full colour display.

A 320 x 240 display has 76,800 pixels, and each pixel has 16 bits (RGB565) of colour information, for a total of 1,226,800 pixels or 153,600 bytes per LCD screen/page.

The LCD controller I use supports a max SPI clock of 40 Mhz resulting in taking 0.180 seconds to draw each page. By only "drawing" the parts of the screen that change, the display updates around 30 times per second.

To make the best use of all clock cycles, I use a RTOS (real time operating system) which allows pre-emptive multitasking. This allows me to run multiple tasks at the same time.

The tasks I have set up are: reading the CAN bus, receiving Bluetooth data, and drawing the display. They all run independently and at full speed. Nice!

Also, since the ESP32 has 2 cores, core 0 is dedicated to handling all Bluetooth communications, and core 1 handles reading the CAN bus and rendering the display.

Anyways, I'm glad to share the details...

Oh, derp! I was thinking esp8266 which didn't have spi capabilities *facepalm* - kinda the little brother of the esp32. I do think I have some 32s laying around from a weather station project I was working on but never finished. Can't wait to see the full published doc - if you need any 370 guinea pigs, feel free to drop be a line.

Thanks for the offer, I will keep that in mind.
Since I am in the Toronto area, I will be testing in this area first :)

Here is an overview of our Bluetooth Sensor Server.
This provides an easy way to convert any wired pressure/temperatures sensors to Bluetooth for our LCD gauges / mini-dash.
-AND-
This means you don't need to figure out how to get a wire from the engine bay, through the fire wall and into the interior of the car.
​​​​​​​https://youtu.be/U_kH3K_C2AE

It's coming along great Frank. Have you decided on what size screen you're going to use? There are a few of us that would like to mount it in the existing cubby location and don't want it to be too small

Thanks!
Tell me what size you would like and I will see what is available and potentially acquire a few for testing.

Let me do a quick survey and I'll get back to you. Thanks

Hey Frank, I think somewhere around 4" x 6" would work out really nice. You could set up a screen with just 2 gauges per screen or multiple gauges per screen (like Ecutek dashboard) can't you? For example, oil pressure and water temp. If so, it would be nice if those could be enlarged to a little under 3" diameter

Thank your for doing this!
I will investigate what my options are in that size.

i think I would only really want a single page.

maybe two large gauges side by side. With 3 smaller gauges to the right and left
total 8 gauges.

Could also have a bar gauge across the bottom. Or some number only gauges in there as well.

I think what would be quite interesting is to be able to set warning values for gauges on the other pages.
So that when a warning value is hit it would maybe flash red and switch to the other page. Then set a warning threshold that when hit would return the system to normal mode and show the default page again.

So many fun things you can do with a programmable screen than just show a set number of gauges on it.

https://cdn.shopify.com/s/files/1/07...g?v=1482425019

This has almost been pretty cool dash style to me. Theres 4 bar gauges across the top
one on either side of the tach. and 3 number value displays to either side of the tach.

these style gauges are also pretty nice
a gauge around the outside as well as a number value inside
https://www.innovatemotorsports.com/...lPressTemp.gif

If a touch screen is used you could enable pressing onto a gauge to swap through a list of gauges. rather than swap through full screens. similar to how some physical gauges work with a button to switch value.

Thank you Frank

https://youtu.be/eJBDXjI5Zu4?t=59

these circular displays would be great for this.

Thank you SeeThruHead and redondoaveb for the suggestions and ideas.
I appreciate it!

SeeThruHead:
A display that is "inspired by Motec" could be done down the road. It has a really nice layout!

Also, I have looked into round LCDs displays to replace all of the 370z triple gauges, with any data item you would like.

As I understand it, the factory triple gauges are difficult to remove and installing LCD gauges would not be easy. My first preference is "plug and play" solution as it greatly reduces installation errors. From what I have seen, many don't seem to understand electricity/proper wiring and do silly things.

Right now I need to focus on getting out what I have been working on for the last year: the Bluetooth gauges for Oil pressure, diff oil temp and other CAN bus data for the G37. Since I have easy access to one (my car in the garage), the LCD enclosure is easier to model and to test.

Speaking of testing, we have developed a new add on for the G37.
A manual transmission Gear Position Indicator in the FACTORY cluster:

Plug & Play, Manual Gear Position Indicator for the G37: MotorvateDIY Garage Ep.43
https://youtu.be/hd8F5H_PcFc

This will be an option in the LCD gauges / mini-dash, or a lower cost stand alone device the size of a small ELM327 and it is plug and play via the OBD port.

I have been driving standard for 40+ years and don't need to know what gear I am in.... However, I sure enjoy seeing the gear number in the factory display!!

One page that could be really neat for track folks is. 4 squares showing tire load on each tire.

Would install 4 linear potentiometers on the cars suspension. connect to your bluetooth server. send values to the display. Set the motion ratio and spring rates for front and rear somehow. And calculate the load for each wheel based on suspension compression.

That's an interesting idea... I would see if a laser-ranging module could be used for suspension travel, much cheaper and easier to install.

Once the gauge development/testing is done, I think the next project it a real time tire surface temperature display using an IR array sensor. Tire temps are a very useful tool to suspension tuning.

For now, my focus are the gauges and a standalone G37 MT6 gear position indicator (displays 1-6 using the factory cluster)

Plug and plug and that slots in front of the dot gauge would be ideal for me. If it was going to have different pages we could go through that would be great (using the stock button for the bonus). I could see 3d printing a bezel and just a friction fit though could see screwing it in later if it was reliable.

Otherwise a 'main page' showing fuel and coolant temp, outside temp and TPMS would probably be my main page.

Something with mpg, range, etc would work too.

Small update:
Wouldn't it be nice to have a "VVEL Gauge" that shows the requested and actual valve lift/duration?
Well, since the ECU controls the VVEL module using a dedicated CAN bus... that got me thinking.

From a past trip to the scrap yard, I have a VVEL module which I wired up to a G37 ECU on my test bench. This allows me to verify wiring and CAN bus IDs by module.
There are just over 1,200 CAN bus messages per second *just* on the VVEL CAN bus, which is a data exchange of about 170,000 bytes per second.

The next step it to record my G37's VVEL CAN bus and then start the reverse engineering!!

NOTES:
• The "ELM327" looking device is the CAN bus to Wifi tool I made.
• I am aware that the typical tuning apps show these values
However, it may be a useful troubleshooting tool as the VVEL CAN bus messages are sent 100 times per second, so you can see everything that is going with quicker updates than an app.

http://www.the370z.com/attachment.ph...1&d=1653596575