Speeduino

I'm building a turbo rock crawler using my old 2000 Jeep 4.0 and want a few hard guages (oil pressure, engine temp) in case the tablet dash craps out on the trail. I know there are some extra ouputs, but I'm having trouble finding information on driving gauges (other than the Tach output).

Are there any IO boards that have been made that could drive gauges? If not, is it feasible to pull data from the Speeduino to a nano and drive gauges through the nano? Thanks for any help in advance!

I run a mechanical gauge for my need to know instruments. Oil light and Temp.

Your digital dash will most likely connect to the other serial port using blue tooth or similar, there is quite a lot of info if you search up serial 3 on this forum or the manual. This is the same port you would use to send data to a nano or similar, so might cause problems

To get oil pressure into speeduino you will need to add a oil pressure unit, only recently implemented in the speeduino code.

There is a GPIO module that can drive extra I/O. Lots of info in this forum on that. search GPIO

Hope this helps.

The outputs can't drive a gauge.

If you want a guage it's either pull the info direct from speedy or separate sensor and gauge.

If its an old fashioned (non-stepper) It can be done by using a PWM output to drive a current sink to replicate the sensor or rip the insides out of the gauges and PWM the gauges directly through a resistor. If its a stepper then its a bit trickier.

Take a look at this:

viewtopic.php?f=15&t=3070&p=37139&hilit ... per#p37139

Thanks for the help!

Looks like DXcontrol will give me what I need.

My next question would be, as stum mentioned, would a GPIO connection be using the same serial port as the bluetooth module hooks up to? I know a mega2560 utilizes multiple serial ports, but I'm not sure how a Speeduino parses those into the board.

There was talk about an OBD2 compatible datastream, I think it may only have been implemented on Teensy, that would allow the use of a universal OBD gauge.

At the moment only teensy natively supports the OBD2 data on its canbus port.
You can achieve the same thing on a mega2560 using my gpio add-on. You need to use the gpio STD version , this connects via serial3 to the speeduino mega. It adds the canbus port and the OBD2 capability.

Typically most people connect the Bluetooth to serial0 on a mega , that way they have TS connectivity ( or msdroid) .

dazq wrote: ↑Wed Oct 21, 2020 7:18 pm At the moment only teensy natively supports the OBD2 data on its canbus port.
You can achieve the same thing on a mega2560 using my gpio add-on. You need to use the gpio STD version , this connects via serial3 to the speeduino mega. It adds the canbus port and the OBD2 capability.

Typically most people connect the Bluetooth to serial0 on a mega , that way they have TS connectivity ( or msdroid) .

This is exactly what I need, thank you for the explanation. My board comes in today so I can start playing with stuff.

Just to clarify.

Mega 1(Speeduino Mega): Will have the bluetooth hooked to serial0
Mega 2(GPIO mega): Will connect to the Mega 1's serial3?

The 0.4.4C looks to have a dedicated set of through-holes labeled for a bluetooth module. I'd assume that goes to serial0?

Nabors wrote: ↑Fri Oct 23, 2020 6:06 pm

dazq wrote: ↑Wed Oct 21, 2020 7:18 pm At the moment only teensy natively supports the OBD2 data on its canbus port.
You can achieve the same thing on a mega2560 using my gpio add-on. You need to use the gpio STD version , this connects via serial3 to the speeduino mega. It adds the canbus port and the OBD2 capability.

Typically most people connect the Bluetooth to serial0 on a mega , that way they have TS connectivity ( or msdroid) .

This is exactly what I need, thank you for the explanation. My board comes in today so I can start playing with stuff.

Just to clarify.

Mega 1(Speeduino Mega): Will have the bluetooth hooked to serial0
Mega 2(GPIO mega): Will connect to the Mega 1's serial3?

The 0.4.4C looks to have a dedicated set of through-holes labeled for a bluetooth module. I'd assume that goes to serial0?

Yes.