Any raspberry pi-ists?

[Tinbasherdan]

I’ll start by saying my computer knowledge extends to ebay and Amazon.....

However, looking at what I can do for gauges in the Landy and have come across autopi, however it requires OBD II input, which I obviously don’t have. Is there any way of utilising standalone electric senders to provide the necessary info? I’d like to just have one unit that can play tunes, do nav and display temps and pressures for oil, air and water

 

[gaz1]

@Kayos

he uses raspberry pi alot

so you may get some good info from

 

[Kayos]

Raspberry pi might be a bit overkill (although that is a my favourite kind of kill)
Would be good if you wanted a small touch screen.
I built an Arduino gauge that reads various sensors and outputs to a 2 X 20 display for the D2

 

[Tinbasherdan]

Raspberry pi might be a bit overkill (although that is a my favourite kind of kill)
Would be good if you wanted a small touch screen.
I built an Arduino gauge that reads various sensors and outputs to a 2 X 20 display for the D2

It would be in place of a double din head unit so a pi would work well I think. The d2 would have obd thoigh wouldn’t it?

 

[Tinbasherdan]

Also, I would prefer the sort of graphical display the r pi can provide, over the dinky little one on the arduino

 

[Dev]

Unless you had a raspberry pi and touchscreen lying about I think it’s possibly more work than it’s worth - I bet you can get an in-car version of those android TV boxes

edit: yep

 

[Tinbasherdan]

Unless you had a raspberry pi and touchscreen lying about I think it’s possibly more work than it’s worth - I bet you can get an in-car version of those android TV boxes

I can but not one that will also display data from the engine etc. I am wondering if you can make an arduino emulate an obd output from analogue signals and feed that into the carpi?

 

[Dev]

I can but not one that will also display data from the engine etc. I am wondering if you can make an arduino emulate an obd output from analogue signals and feed that into the carpi?

Don‘t know- that might be a challenge I don’t know how common it is for anyone to want to do that without OBD. You can definitely read analogue voltages but it would depend on your sensor output voltages. A pi can read analogue inputs directly but there’s more coding involved.

 

[Tinbasherdan]

I have a feeling that unless I can find a nice person with coding ability, it’s a non-runner really. I wanted to get away from having a load of analogue gauges on the dash if I’m honest and just have a neat package

 

[Kayos]

I have a feeling that unless I can find a nice person with coding ability, it’s a non-runner really. I wanted to get away from having a load of analogue gauges on the dash if I’m honest and just have a neat package

I've got a 7" Rpi touch screen so double din size. Yours for the postage

 

[Tinbasherdan]

I've got a 7" Rpi touch screen so double din size. Yours for the postage

That’s a kind offer, I’ll sort it out with you shortly

 

[bigegg]

I have a feeling that unless I can find a nice person with coding ability, it’s a non-runner really. I wanted to get away from having a load of analogue gauges on the dash if I’m honest and just have a neat package

Outside the box:

Use a rasp-pi, but run "home assistant" on it.
Set up a dashboard with "gauge" cards that display the sensor readings you want.
You don't need to be able to "program".
Much of it can be done via GUI.


Not sure how many analogue inputs that a Raspi can do without adding extra cards???

An ESP32 has 16??? ADC pins (so 16 sensors) and can connect to a PI over WiFi/BT (or cabled serial link) if you needed more. (I'd use MQTT to transfer the data)


<Edit: if you don't want "analogue" gauges, there are many other ways of displaying the data - you can even swap from one to another easily - and you wouldn't need a display, it could be done on your phone.>

 

[sako243]

There's plenty of Bluetooth or USB OBD apps for Android so if you get an android head unit you can install those apps and get a compatible diagnostics tool.

 

[Fastdruid]

I can but not one that will also display data from the engine etc. I am wondering if you can make an arduino emulate an obd output from analogue signals and feed that into the carpi?

So, in theory, yes...but you're going to need to be a bit better with the hardware and coding than it sounds like you are.

You could take the basics of one of the ELM327 type adaptors and use an Arduino to fake it. The ELM327 is pretty basic in what it does[1] and it would be pretty easy to do...if you're good with code anyway. You might need to re-use the actual USB chip (FTDI FT232RL maybe?), although equally you might be able to totally fake it with an Arduino or maybe better still a Teensy as that can emulate USB devices.



[1] At the front end, the back end is complicated but essentially from the front end perspective it is an a serial device that uses AT code[2].
[2] https://www.elmelectronics.com/wp-content/uploads/2016/07/ELM327DS.pdf

 

[Tinbasherdan]

So, in theory, yes...but you're going to need to be a bit better with the hardware and coding than it sounds like you are.

You could take the basics of one of the ELM327 type adaptors and use an Arduino to fake it. The ELM327 is pretty basic in what it does[1] and it would be pretty easy to do...if you're good with code anyway. You might need to re-use the actual USB chip (FTDI FT232RL maybe?), although equally you might be able to totally fake it with an Arduino or maybe better still a Teensy as that can emulate USB devices.



[1] At the front end, the back end is complicated but essentially from the front end perspective it is an a serial device that uses AT code[2].
[2] https://www.elmelectronics.com/wp-content/uploads/2016/07/ELM327DS.pdf

A bit is a bit of an understatement I do however have a colleague who teaches programming so I’d hope he can help me do it

 

[bigegg]

How old a "landy" are we talking?
And what sort of sensors does it have already?
"Standalone" sensors *should* be able to be fitted to give analogue voltage readings for most things?

(I'm going by my foray into getting an accurate radiator temp gauge for a MK2 shogun - easy enough to add thermocouples or pressure transducers to pipework?

<Edit: like this
https://www.digital-speedos.co.uk/a...hose-type-choice-of-sizes-available-p251/s375
>

 

[Dev]

So, in theory, yes...but you're going to need to be a bit better with the hardware and coding than it sounds like you are.

You could take the basics of one of the ELM327 type adaptors and use an Arduino to fake it. The ELM327 is pretty basic in what it does[1] and it would be pretty easy to do...if you're good with code anyway. You might need to re-use the actual USB chip (FTDI FT232RL maybe?), although equally you might be able to totally fake it with an Arduino or maybe better still a Teensy as that can emulate USB devices.



[1] At the front end, the back end is complicated but essentially from the front end perspective it is an a serial device that uses AT code[2].
[2] https://www.elmelectronics.com/wp-content/uploads/2016/07/ELM327DS.pdf

You could use esphome on an esp32 and wifi it to a raspi running home assistant, coding wise that wouldn’t be too bad.

 

[Tinbasherdan]

How old a "landy" are we talking?
And what sort of sensors does it have already?
"Standalone" sensors *should* be able to be fitted to give analogue voltage readings for most things?

(I'm going by my foray into getting an accurate radiator temp gauge for a MK2 shogun - easy enough to add thermocouples or pressure transducers to pipework?

<Edit: like this
https://www.digital-speedos.co.uk/a...hose-type-choice-of-sizes-available-p251/s375
>

It’s a k ref defender with a 98 Cummins engine. Usual senders, oil pressure, coolant temp but I want to add air pressure and boost pressure

 

[bigegg]

You could use esphome on an esp32 and wifi it to a raspi running home assistant, coding wise that wouldn’t be too bad.

How well would WiFi work from (say) inside an engine bay to cab?
4 wire serial connection could be done with alarm cable, or 4-core flex if you wanted something a bit "beefier".

 

[RaceDiagnostics]

This is a lot more complicated than you think, first you need to know the transfer function of the sensor voltages to the actual measured values, where will you get that?

It needs to be made robust for an automotive environment, the pi is not. You will indeed interface electronics designed to accommodate this so as not to blow up your pi.

You need custom code to interpret the voltages from the sensors and map them to actual values.

This is a lot of work and will be expensive unless there was a large market for the end product.

I did a project like this 15 years ago and it was a lot of effort.

I'm sure if you do a bit of googling you will find that someone else has already done it and has a solution. Much easier to start from a product that almost does what you want and take it from there.