feature request: potentiometer boost control...

[JoseMiguel]

As some probably know, im always looking for new ways to get the most out of boost control from the MS units...

Here in my country, there is a big Haltech ECU base. I also program this units and find them in some ways superior and in some ways inferior to MS units. The fact is that many people here keep me telling that they wish to have a potentiometer "boost control" unit like in the haltech ECU. The fact is that most haltech units come with a small potentiometer that you can connect in an analogue input (0-5V) and control various features of the ECU, like fuel trim and boost control.

So what I did is fairly simple. I disconnected my TPS and set the accel enrich to MAP mode (TPS gives me better results overall) and deactivate all other features that use TPS as a base (like idle control, idle advance settings...). I connected a potentiometer to the TPS input, calibrated it and voila! I get a potentiometer-activated boost control. With the potentiometer, I can set the position of the Y axis in the boost duty (open loop) map. Of course, the map has been set up to get more boost with more "tps" (in this case, the potentiometer).

I would love to have this feature WITHOUT having to sacrifice the TPS input and the features that need TPS control...

the question is:

1... is it possible to make a circuit in a MS unit for a spare analogue 0-5v input?
2... if that can be done, is it possible to include a feature so that we can choose the Y axis of the boost table and select the spare input?

thanks!

[Nitroking]

Lol.. Smart one.. I like it!

[JoseMiguel]

Bump

[Matt Cramer]

MS3 already has a table blending mode that will blend between two boost tables based on a sensor input.

http://www.msextra.com/doc/ms3/tables.html

Not sure this can be ported to MS2 however.

[JoseMiguel]

I have used the blending boost table in a few ms3 setups, works nicely. But in this case no blending would be necessary. Just the same table as always with the y axis controlled by an analogue input that is not the tps

[JoseMiguel]

no thoughts on the original question?

thanks

[dontz125]

Adding a POT to one of the spare ADCs is easy; just duplicate the TPS filter circuit shown on the schematics in the proto area. Changing the Y-axis options on the Open-loop boost table to include that spare ADC is a little more involved, as it requires changing the code. For someone who knows what they're doing, I would suggest it should be rather straightforward. For a code-free zone like myself ... not gonna happen!

[JoseMiguel]

Adding a POT to one of the spare ADCs is easy; just duplicate the TPS filter circuit shown on the schematics in the proto area. Changing the Y-axis options on the Open-loop boost table to include that spare ADC is a little more involved, as it requires changing the code. For someone who knows what they're doing, I would suggest it should be rather straightforward. For a code-free zone like myself ... not gonna happen!

What is the function of analogue inputs? im not very clear with that

I found this in the new manual



looks like a very simple circuit, and im guessing it is in fact a 0-5v input. I should be able to connect a pot to this input, am I correct?

in that case, all that is left is modding the code so that I can use this input instead of using the TPS signal.

[dontz125]

The analogue inputs read a 0-5v signal; the main inputs are MAP, O2, CLT, IAT, TPS, and (internal only) VBat. The MS2 has 8 inputs, with two left as spares.

[JoseMiguel]

Thanks

Im going to build the circuit and "try" to modify the boost control tables so that the y axis would be the spare input

[jsmcortina]

Code: Select all

            if ((flash4.OverBoostOption & 0x08) && (flash4.FlexFuel & 0x1)) { // flex/boost option
                if (outpc.tps > flash4.flexboosttps) {
                    yaxis = outpc.fuel_pct;
                } else {
                    yaxis = 0;
                    targ_load = outpc.baro;
                }
            } else {
                yaxis = outpc.tps;
            }

Around line 230 in ms2_extra_misc.c for closed loop boost. Set yaxis = (something else) It is expecting a number 0-1000, so reading the raw ADC value (0-1023) may well be close enough.

James

[JoseMiguel]

Hi james, thanks for the answer. I have worked in MS code before, but im a bit lost with this one

im working with the open loop part, it gets easier to test. Here is the code

Code: Select all

boost_ctl_duty = intrp_2dctable(outpc.rpm, outpc.tps, 8, 8,
                    &pg5_ptr->boost_ctl_pwmtarg_rpm_bins[0],
                    &pg5_ptr->boost_ctl_pwmtarg_tps_bins[0],
                    &pg5_ptr->boost_ctl_pwm_targets[0][0], 0);

from my understanding, im looking to "read" the spare analog, so I should replace "outpc.tps" with "outpc.[something]", im guessing something is "port0" or whichever port im using... is that correct?

and then, how do I "determine" that the analog input im using corresponds to port0 (or 1 or 2 or whatever)

after this, I should be able to put the table with values betweeen 0 and 1000 depending on the potentiometer output....

[racingmini_mtl]

No. You will be using adc6 or adc7. And the value will already be between 0 and 1023 (which should be close enough to 1000).

Jean

[JoseMiguel]

No. You will be using adc6 or adc7. And the value will already be between 0 and 1023 (which should be close enough to 1000).

Jean

assume im using JS4... then:

Code: Select all

boost_ctl_duty = intrp_2dctable(outpc.rpm, outpc.adc6, 8, 8,
                    &pg5_ptr->boost_ctl_pwmtarg_rpm_bins[0],
                    &pg5_ptr->boost_ctl_pwmtarg_tps_bins[0],
                    &pg5_ptr->boost_ctl_pwm_targets[0][0], 0);

is that right?

BTW, what is the difference between outpc.gpioadc6 and outpc.adc6. Sorry for the questions.

thanks again

[racingmini_mtl]

Look at the schematics; JS4 is ADC7.

The gpio variables are for values read from a CAN device.

Jean

[slyrye]

It would really be greatly appreciated and very helpful if this type of boost could be implemented on MSGPIO, thereby reading ADC from MSGPIO via CAN

[slyrye]

or Boost per gear using MSGPIO to be interpreted and executed by MS2 via CAN...! would be really awesome function...!