MEP-803A Digital Gauge Cluster Development

[Icesythe7]

Figured I would start a thread on converting my mep-803a to be more like an mep-1040 since I want one and can't afford one, this will be to document my progress.

Goals are for a single larger touchscreen to view all data as well as via bluetooth/wifi on phone, idea is to remove current gauge clusters and 3d print a screen holder that will use the existing holes as mounting holes as to not make any cuts/modifications to the original structure so that it will be 100% reversable. Once initial testing is done and a 3d printed mount is created I will probably design a pcb and goal is to use off the shelf parts and modules so that assembly is simple and easy for anyone.

Day 1 progress is a simple meter to monitor coolant temp as that is the easiest needle to move and test the proof of concept (still needs some slight adjustments and resistor tweaking as voltage ref is unstable atm hence why needle bounces), here is a video of some proof of concept testing (load prolly should mute unless you want to hear generator running.)

Gauge seems to just use a voltage range of 0-12v to move the needle which can be easily accomplished and read with any mcu using a voltage divider and some simple math...

float read_voltage(const uint8_t pin) {
  return (float)analogRead(pin) / 4096.0f * 24.457f * (115000.0f / 114300.0f); //(assumes 3.19v output with voltage divider of 115000 ohms (114300 actual))
}

 

[Icesythe7]

Working on GUI while waiting on parts from china, end result will be obv a larger touchscreen but trying to keep it authentic to the 1040...progress thus far...

 

[Digger556]

I like where this is going. Great project!

I was looking at my 802 the other night and thinking about something similar.

 

[Digger556]

It's getting harder to find replacement gauges and a prebuilt system (screen) that could take the place of those gauges would be great, especially if the costs could be kept to a hobbist/consumer price point for the screen. Also if the back end bits were modular, that would help servicing and keeping spares on hand.

I was thinking about replacing the entire panel with a custom unit. It is just sheet metal that's been hard black anodized, so that would be easy to pull together in Solidworks.

 

[Light in the Dark]

Problem is none of these off the shelf items have been ruggedized, the constant NVH of a running machine is the biggest thing to contend with.

 

[FarmingSmallKubota]

Also the AMMPs screen does a whole lot more than just give maintenance and readings, its the brains and logic of the whole machine. Everything behind your panel on the 8xx series is in that computer box on the AMMPS machines.

 

[Icesythe7]

Problem is none of these off the shelf items have been ruggedized, the constant NVH of a running machine is the biggest thing to contend with.

Right building something for the 803/802 to replace gauges is easy and cheap (pi pico w and a screen is like $25 bucks shipped) issue with price comes into play when you have to protect against the elements and emf.

Also the AMMPs screen does a whole lot more than just give maintenance and readings, its the brains and logic of the whole machine. Everything behind your panel on the 8xx series is in that computer box on the AMMPS machines.

Correct but I am just imitating the look of the ammps screen to replace gauges on the 80X machines not making a replacement for ammps machines