RPM with Dash2, DL-1 and ECU interface

[skydragon]

I have a Dash2, a DL-1 and a Emerald K3 ECU interface fitted to my car.

They have been installed and working ok for some time.

The Dash2 has an analogue RPM input fed into it and up until now I have always had this as the selected RPM input for the Dash2. With a pulses per rev of '2' set in the dash2 config sw, The dash2 display matches up 100% with the actual engine revs. The rev display and shift lights work well.

If I try to log RPM data on the DL-1, the resulting data is always then displayed in the simulation sw as approx 30% too low, when compared to the actual RPM. eg. 1000rpm is displayed as approx 700rpm with 2 pulses per revolution selected in vehicle options. I've tried messing around with the pulses per revolution setting in vehicle options. but the result is either significantly higher or lower than the true rpm. why is this? If I look at the logged RPM data in the DL-1 and set no smoothing in the variables manager the resulting RPM trace looks very noisy, with positive going peaks over the baseline (correct) rpm value. Why does the Dash2 display the correct RPM values on screen, yet not output a 'clean' value to the DL-1 for logging? Is there something I can change in the settings to cure this?

I have also tried using RS232 RPM data from ECU to the Dash2 and this also works ok. The dash2 display matches up 100% with the actual engine revs With a pulses per rev of '1' set in the dash 2 config sw, .

I now want to log ECU RPM on my DL-1 as data.

If I try selecting ECU RPM in the analysis software (in the variables manager), there is no ECU RPM data present at all. I don't understand why the Dash2 would receive and display ECU RPM data ok, yet the DL-1 does not seem to be able to receive or log it.

(In the DL-1 config software, I have selected RPM as 'disabled' in both memory card and in serial as per the instructions) i also have 'decode data' ticked on the serial port tab of the config.

Ideally what I would like to do is use the analogue RPM input on the Dash2 for the RPM on the Dash2 display and in parallel, simultaneously use the DL-1 to log ECU RPM data.

I can select RS232 data on the Dash2 display and use this to drive the display and then also use the DL-1 to log the RPM channel. Unlike when I use the analogue RPM as the Dash2 input, the resulting logged RPM values in the simulation sw are all correct. But it means I've got to have my DL-1 switched on all the time to then get any RPM output on the Dash2 display which is something I'd rather avoid.

Can you please help me?? - How do use the analogue RPM input on the dash2 to drive the RPM display on the Dash 2 screen and at the same time log ECU RPM data on the DL1.

Failing that, how do I get the DL-1 to log the analogue RPM data off the Dash2 accurately?

Probably finger trouble on my part. Any ideas?

[osborni]

I send the RPM to both the DL1 and the Dash2. Just a simple Y wire. Works fine.

[Support]

It might be that the DL1 is seeing to values for RPM and the analysis software RPM filtering is averaging them out making it look like a sensible RPM trace but just an odd value.

Please can you email me a sample file for to check kieran@race-tech...

[skydragon]

I send the RPM to both the DL1 and the Dash2. Just a simple Y wire. Works fine

I could do that, but I specifically want to log ECU derived RPM data.

It might be that the DL1 is seeing to values for RPM and the analysis software RPM filtering is averaging them out making it look like a sensible RPM trace but just an odd value.

I'm sure it is. But I don't understand why the Dash2 will display the correct RPM reading, yet the analysis software won't.

My main question is, why is there no ECU RPM data in the DL-1 logged data?

I've emailed a run file to you, to review.

thanks for your help.

[osborni]

Start isolating variables. Send one stream of data at a time to one device and see what happens.

[Support]

thanks for the logged data. If you remove all filtering and remove joining graph point in an XY graph display RPM you can see there are 2 RPM traces.

The DASH2 is outputting the 2 pulses per rev RPM data on its serial port and the ECU interface is outputting 1 pulse per rev RPM data and the DL1 will just record them both.

If you have a CAN interface the channels are selectable so you could just move the RPM from ECU to another channel. On the serial interface they are fixed.

Your options are...
1) Have the RPM on the DASH2 coming over RS232 which will stop the DASh2 transmitting RPM and record the 2nd RPM source on the DL1 frequency channels.
2) Disconnect the the DASH2's transmit from the ECU interface and again record the second source of RPM on the DL1's frequency inputs.

Kind regards,
K