Custom instrument panel face?

[3175375]

So trying to put this in terms that I (and others ) can understand. I'm going to get it wrong so please correct me. Raspberry Pi and Arduino are the operating systems that run a mini PC, kind of like Windows on a desktop or laptop. But these operating systems are open to modification and customization as well as completely separate programs written by users. A dashboard display would be one of these custom programs written/coded by a user. Key parts of this, besides the all important custom code, would be connecting to the display and getting the inputs (speed, rpm, etc) from the car itself. In a new car a OBDII port would typically be used?? but with old car we need electrical/analog signals to be converted to digital so the code can read and understand it. These interfaces pieces would have to be physical hardware pieces/chips not typically a part of these mini PCs.

So tell me if I'm even close. And if I am why use this versus a Microsoft windows mini PC? And could just the needle be programed to move on top of a digital picture of an existing gauge? thnx. Car PCs are very interesting and a little unnerving consider what they could control. Would give a new meaning to "crashed" my computer today. I need skin grafts but avoided blue screen of death.

Also found what I think is a good price on a RBPi kit. $80 after code LABIST1

You are close to being correct. I believe they are microcontroller operating systems that loads the assembly language instructions into the micro controller. They use higher level languages for the developer to develop the control algorithms in languages similar to C++, etc.
Various configurations of the physical hardware exist that include A/D converters, D/A converters, discrete inputs and outputs, and various other interfaces (Bluetooth, WiFi, Ethernet, RS-232, etc.

I used a few microcontrollers, the last being a Z80 based system to control a liquid cooling system for a radar in a flying testbed.

 

[WissaMan]

Arudino and Raspberry Pi are the hardware pieces. They come in many different models which vary according to base features, memory, and speed. Usually the Arudino is referred to as a "microcontroller". It has a fairly basic CPU, some flash memory for code and a small around of working RAM. The Raspberry Pi on the other hand, is a full fledged computer that can run Linux. They both can interact with the outside world through I/O pins that can be controlled with software. The Arudino has A/D built into it's chip. The Pi needs A/D added on.

To program the Arudino, you write the code (similar to C++) on a PC/Mac/Linux, compile, then upload to the Arudino via serial cable or USB/serial. You can run a serial monitor so it can take orders and talk back to the PC. It has no video built in and sound is just simple beeps and buzzes (al la Apple ][). Lots of time they run headless (no display) or you can connect a small LCD or LCD display and feed it with serial. The advantage (to me) of the Arudino is it is more basic and boots almost instantly when power is applied. It doesn't have to load an OS and then your program. It also has a lot of good software libraries for interfacing with sensors, motors, etc. You can add hardware modules like WiFi, SD card readers, bluetooth, etc. but I haven't worked with any of those.

Since the Pi is an actual computer, you can create programs on it in a variety of languages (C, assembler, Python, you name it). I chose Python because it seemed relatively easy to pick up on and there's lot of software libraries and tons of knowledge out there. Since so many people tinker with the Pi, just above every question I've had so far that I searched on, I found multiple examples of people asking the same questions and getting usable answers, which is a big help when starting out.

 

[WissaMan]

As for using a mini Windows PC vs. the Pi -- I think it would come down to choice and cost. There are small PC's that come in basically the same form factor as the Raspberry Pi. I don't know if they come with some kind of free/stripped-down Windows OS or if you have to buy an actual Windows license. The Pi on the other hand, runs Linux which is free.

I think one reason tinkerers like the Pi/Linux combo because Linux is very customizable in itself. You can run a very stripped down version that doesn't even have a GUI. The more you strip it down, the faster it boots/runs, the more stable, less memory required, etc. Windows on the other hand is very bloaty. I know there are stripped down versions of Windows available that are meant to run on embedded controllers and such but I don't know how easy it is to get a hold of that or cost.

 

[Mike66Chryslers]

What did you use for a voltmeter? I love the work you did. I wouldn't mind doing this on the father in laws 65 sport fury

Thanks! I don't actually know the brand of voltmeter. I bought it used at a swapmeet for this project. I think just about any 2-1/8" face, air-core voltmeter with a 90-degree sweep should work. Just make sure it has a tweaker knob to calibrate the reading. I think they all do, usually a small hole in the back of the gauge to insert a small screwdriver to adjust a potentiometer.

 

[bnz84]

Ok, thanks guys. That makes more sense. Its easy enough to google these same questions but its good to have it filtered through a car persons vocab. I saw a video of a guy using A RBpi and yes, like a windows PC it still had to boot and access the program and shut down, etc. So am I correct in saying that while they make analog to digital dash converters the problem is the display itself and code that controls it. Its not customizable and not classic looking. Hence the entire purpose of this thread. You need some place to load your custom code for you custom display? I might be getting it now. I too have looked into hacking other gauges to function with existing OEM display like the example on page 1. But never went so far as creating a display via code.

 

[jake]

I bought a set of speedhut gauges. I am thinking of something like this. Still trial and error.

 

[3175375]

Ok, thanks guys. That makes more sense. Its easy enough to google these same questions but its good to have it filtered through a car persons vocab. I saw a video of a guy using A RBpi and yes, like a windows PC it still had to boot and access the program and shut down, etc. So am I correct in saying that while they make analog to digital dash converters the problem is the display itself and code that controls it. Its not customizable and not classic looking. Hence the entire purpose of this thread. You need some place to load your custom code for you custom display? I might be getting it now. I too have looked into hacking other gauges to function with existing OEM display like the example on page 1. But never went so far as creating a display via code.

The boot up time is one of the requirements that differ from the pc and micro controller based systems.
For a car, it’s not critical, but for other systems, like an aircraft, missile or a spacecraft, startup time is critical.

more of a ‘what do you like / want’ for a car.

 

[WissaMan]

The boot time for my Pi is less than 30 seconds. I don't have it set to auto-run anything yet, so there'd be a little time added on for that as well. The boot time for an Arduino is only a couple seconds. But if you want immediate action, you could just leave them powered up but in a low-power sleep state, kind of like an ECU in a modern car. Or maybe set it to shut down after set period of inactivity to conserve the battery.

 

[SuperDave]

I'm saying screw it all, I'm gonna yank the entire dash from my 73 Newport, dremel off the left section for the wipers & light switch and craft my own dash from a textured acrylic panel (via Amazon: https://www.amazon.com/dp/B07BCVJ3W9?ref=ppx_pop_mob_ap_share) and a full set of gauges from eBay (6 Gauge set Speedo Tacho Fuel Volt Meter Oil Pressure Temp Black Red Backlight | eBay). Yes they do stock the correct 73-10 ohm gas gauge for our Mopars, you have to mention this during the checkout process and they will swap it out when it ships to you. It does come from China so expect to wait a couple weeks for shipping, but a full set of electric gauges under $200 makes it worth it.
Since I'm going to do without AC, I can delete the vents, cap off the ports behind it and open up additional real estate for relocating the radio (also aftermarket, ultrathin mechless design, it accepts a thumbnail SD card for storing MP3s & a usb port). Being so light, it won't hang heavy on the plastic or need support. This allows me plenty of room for full gauges.

For shits and giggles, I'm making this a HIS & HERS dash, full gauges AND idiot lights. The oil sending unit has 2 pins, one for the electric gauge and the other to run an LED when pressure drops below 11psi. I'm using both water ports for the sending units, one for the gauge, the other is still wearing the original hot/cold sending unit to power a red & blue LED. I'll use the Low Fuel warning light module for the gas light, and BigMoparJeff pointed me to a circuit diagram for a low voltage light I can put together myself. I even have a ProComp shift light I'm butchering to install a big bright yellow LED next to the tach. I even got a matching clock. No LED for it, but I will install a micro button where the light would be for setting the time. Only the speedo won't have a light, but there will be an additional LED for the brake warning light. The 200 MPH GPS speedo incorporates its own turn signal arrows & high beam indicator.

I will try to incorporate the shifter indicator, cut out the window and epoxy it behind the panel, since I already deleted the column handle and installed a floor shifter. I'm not using the decals that came with the shifter kit, I like how it looks like a 4 speed boot, but at present the factory linkage is also intact so the dash window still shows the proper gear. It also locks it in park when the key is removed, which is nice.

When I'm done I'll post pics for y'all to drool over.

 

[WissaMan]

Cool -- I love this kind of ambition! Are you going to do any heat forming of the ABS sheeting?

 

[SuperDave]

Are you going to do any heat forming of the ABS sheeting?

@WissaMan, I shouldn't need to, the original dash of the '73 is flat so no curves are needed. I will notch/cut out for the climate controls so I can use the heater & defroster. The texture of the ABS panel closely matches the original so it'll look stock, and the generic gauges don't show a brand name, so aside from the digital odometer/hour meter & LED trouble lights next to each gauge, you might think it was stock.

 

[WissaMan]