R32 GTR table
Moderator: Matt
R32 GTR table
Matt, what does the boost duty cycle map do? It's not referenced to rpm or load......
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A better approach to understand oem boost control would be to start with analyzing the boost control hardware itself.
Any sort of dynamic boost control is going to be done using one of two methods, in combination with the appropriate hardware for that method. The two methods that could be used are PWM (pulse width modulation) using a high speed solenoid valve much like a fuel injector except it is metering air instead of fuel, or a stepper motor valve which would allow steady-state metering of the valve orifice to control air flow.
These two (true dynamic boost control) methods vary greatly in the way the ecu hardware would control them. Generally, the main microcontroller (in the case of r32 it would be hd6303) is utilizing all of its available timers, counters, capture and compare match features for fuel and ignition control.
Because these same functions are required for an additional PWM, the system must off-load the task to an external companion processor.
Because the system is built around shared-ram, it is possible for the main microcontroller (hd6303) to perform the simple tasks of deriving an actual value that corresponds to a pulsewidth that would be appropriate for the booost controller. It then places in this value in RAM that is shared with the companion processor(s) which actually turns the value into a real-world pulsewidth that is sent to the valve itself with a certain frequency.
A stepper motor system is a little different, and could potentially be controlled using only the main microcontroller itself, or by a companion processor. The difference between the stepper motor and the PWM is that the stepper motor does not require the timers/counters, but what it does require is quite a few microcontroller pins.
A method I did not mention that could be considered boost control, but not true dynamic boost control, is the utilization of multiple simple vacuum solenoid valves attached to different orifices (manual boost controllers) to provide different boost profiles. These are very easy to control using the main microcontroller using only a few pins, and many oem turbo vehicles use this method (nissan and others). It is also very easy to apply this method to other previously non-boost controllable ecus with a few simple code modifications.
So, what I am getting at is that all boost control is not created equal, in order to discuss it in context, the type of boost control valve must be known. R32, Z32, S14....etc.. may not be the same or even similar.
Check out the valve that is actually controlling the boost/wastegate and go from there.
Any sort of dynamic boost control is going to be done using one of two methods, in combination with the appropriate hardware for that method. The two methods that could be used are PWM (pulse width modulation) using a high speed solenoid valve much like a fuel injector except it is metering air instead of fuel, or a stepper motor valve which would allow steady-state metering of the valve orifice to control air flow.
These two (true dynamic boost control) methods vary greatly in the way the ecu hardware would control them. Generally, the main microcontroller (in the case of r32 it would be hd6303) is utilizing all of its available timers, counters, capture and compare match features for fuel and ignition control.
Because these same functions are required for an additional PWM, the system must off-load the task to an external companion processor.
Because the system is built around shared-ram, it is possible for the main microcontroller (hd6303) to perform the simple tasks of deriving an actual value that corresponds to a pulsewidth that would be appropriate for the booost controller. It then places in this value in RAM that is shared with the companion processor(s) which actually turns the value into a real-world pulsewidth that is sent to the valve itself with a certain frequency.
A stepper motor system is a little different, and could potentially be controlled using only the main microcontroller itself, or by a companion processor. The difference between the stepper motor and the PWM is that the stepper motor does not require the timers/counters, but what it does require is quite a few microcontroller pins.
A method I did not mention that could be considered boost control, but not true dynamic boost control, is the utilization of multiple simple vacuum solenoid valves attached to different orifices (manual boost controllers) to provide different boost profiles. These are very easy to control using the main microcontroller using only a few pins, and many oem turbo vehicles use this method (nissan and others). It is also very easy to apply this method to other previously non-boost controllable ecus with a few simple code modifications.
So, what I am getting at is that all boost control is not created equal, in order to discuss it in context, the type of boost control valve must be known. R32, Z32, S14....etc.. may not be the same or even similar.
Check out the valve that is actually controlling the boost/wastegate and go from there.
ER34 has a boost table similar to S14 with scalers, so you should be able to modify the duty cicle on this
I've finally finished fixing up logging and a few outstanding bugs in the NIStune software and am back to getting Type 4 running Y33/E34 since I have these two ECUs still sitting here on my bench to get going. Y33 is running without dropouts which is good, but doesnt write so I'm looking into that one at the moment. Good ECU to use to compare against ER34 on the logic analyser
I've finally finished fixing up logging and a few outstanding bugs in the NIStune software and am back to getting Type 4 running Y33/E34 since I have these two ECUs still sitting here on my bench to get going. Y33 is running without dropouts which is good, but doesnt write so I'm looking into that one at the moment. Good ECU to use to compare against ER34 on the logic analyser
Update on this Investigate issue
You can only maptrace this by monitoring the value in the consult RAM table and then try and calculate the display... unless we made a custom consult entry to the table, streamed that then printed it
But I probably wont do that.... the moates maptracing stuff will be worked on soon and you can use hardware maptracing for stuff like this if you have one of these units
There is no scalers for this map at all10560 BNR32 Boost map. Find more information
So the value at this address is an index to the mapUses 0x149A as index to 256 byte map (indexed as AB+AB/16)
You can only maptrace this by monitoring the value in the consult RAM table and then try and calculate the display... unless we made a custom consult entry to the table, streamed that then printed it
But I probably wont do that.... the moates maptracing stuff will be worked on soon and you can use hardware maptracing for stuff like this if you have one of these units