Modifying Motronic 2.3.2 ECU hardware and software.

[kymi]

Ok, if that's the case. Why don't you use that same map for NLS? When launching you have revs limited lower and with NLS you're at normal rev limiter.

PS. It's not madness going on in the ECU.

[vwnut8392]

Sorry, I just have to ask. What are you going to do with multiple manually switchable ignition maps? I assume you have found 2 usable maps at the moment, one for your "launch control" and one for normal operation. Isn't it enough? And when switching ignition maps, shouldn't you be changing the fueling also?

working on an idea i have and i want to see if it will work thats all. if i can switch to another map im going to use it for a no lift shift in conjunction with the WOT BOX. i will have full ignition cut with the WOT BOX and timing retard if its needed with another map thats flattened at a certain RPM like i did with the launch control. for me this is a bit simpler than trying to understand all the madness going on in the ECU directly.

[kymi]

Sorry, I just have to ask. What are you going to do with multiple manually switchable ignition maps? I assume you have found 2 usable maps at the moment, one for your "launch control" and one for normal operation. Isn't it enough? And when switching ignition maps, shouldn't you be changing the fueling also?

[vwnut8392]

i know i'll probably hear crickets but i was thinking about ignition map switching again. i already discovered that when grounding pin 5 of the coding connector it will switch over to a different ignition map than normal. what i was wondering is if there is a way to switch to other maps via this wire and resistor or another wire in the coding connector? it just seems there's a who lot of ignition maps and most of them are not really used for anything.

[kymi]

There's map lookup routines on both chips. This thread has more than enough info how to find those and those are pretty straight forward.

Analog inputs are accessed like that on both chips, with ADCON0.

[vincentroyc]

Not sure if you're talking about boost or fuel/ign chip. But these answers will do on both chips.
1. Not sure if I understood you correctly. It depends on the map how the result is used. Some of the values are compared to ram values, some values are directly used for something, some values are used with adaptation, etc.
2. It depends on the input or the data. Analog inputs are not the only way feeding the data to chips. Analogs are easy to find, but you just need to find where those are used. You should check interrupt routines, timers, etc. Internal & external ram, what feeds what.

Hey kymi,

For the first question i was more asking : how does the maps are accessed, i mean are they always refered to with a MOV DPTR, #first_map_value_adress and then based on the values of each axis input it calculate the offset of the wanted value in A and then get the good value with the MOVC A, @A+DPTR?

New question : are the analog input accessed like this :
MOV ADCON1, #channel_number
; and when channel ready
MOV SOME_REGISTER, ADDAT

[prj]

I recommend reading the 80C515/535 user manual before continuing to ask questions which are answered therein.

[kymi]

Not sure if you're talking about boost or fuel/ign chip. But these answers will do on both chips.
1. Not sure if I understood you correctly. It depends on the map how the result is used. Some of the values are compared to ram values, some values are directly used for something, some values are used with adaptation, etc.
2. It depends on the input or the data. Analog inputs are not the only way feeding the data to chips. Analogs are easy to find, but you just need to find where those are used. You should check interrupt routines, timers, etc. Internal & external ram, what feeds what.

[vincentroyc]

Ok here are my questions :
1. Are the maps always accessed throught the address of the firt value then the program interpolate to the good address/value from the converted value of the input?
2. What is the process to read an input? Is the input read throught a specific adress than converted with the adc? Or all inputs are read directly throught the adc?

Thanks

[prj]

You take the maps that are related to boost cut or similar, find which variable is compared and backtrace the ADC read from that variable.

[vincentroyc]

Hey PRJ how can i map the inputs of both chip in the assembly? For example where is the boost voltaGe /input is in the boost chip? I guess they would me in the special function register space where there are some constant defined for ram? Can you guide me a little in this?

[prj]

Yes Rs2 551c boost chip...

The analog input of the tps is put into 0x5d internal RAM and used in many routines (boost control, overboost calculation etc.)

I dont't have much knowledge about the boost chip at the moment. I can tell you from the code which map is read. But i don't know anything about the axes. Just that rpm and tps are used as axes.


Bye

The way it works is, it takes raw ADC and if there is "overboost" it just simply adds a configurable fixed value to the raw ADC value.

So for example your overboost % is 20%.
Let's say throttle is at 60%. With overboost, the total value will read 60%+20% with overboost active.
Overboost activity depends on a number of configurable parameters. IIRC the time counter was rather long at 30 seconds or so by default (it's been a while since I looked at it), so technically the car is always operating in overboost mode. Except one case. When you are flooring it top speed on the Autobahn.
And that's why the overboost mode is there - to reduce the engine heat when on autobahn long WOT runs and make the engine "Vollgasfest".

At WOT, the overboost will push the TPS value over 100%, hence why the last row is also 117% in the maps.
If you want to disable the overboost functionality at WOT you can just make the last two rows read the same in the target boost and N75 base DC maps.

On the RS2 for example, there is no added midrange boost, but after 30s or so of WOT, the boost is lowered at high RPM WOT scenario a little.
Again, this is to prevent overheating of the engine and associated components.

This is all from memory, I have no tuning related material on this PC. Sorry if I made some errors with the exact numbers.

Someday I will write all this up in a pdf... Someday.

[-ice-]

Yes Rs2 551c boost chip...

The analog input of the tps is put into 0x5d internal RAM and used in many routines (boost control, overboost calculation etc.)

I dont't have much knowledge about the boost chip at the moment. I can tell you from the code which map is read. But i don't know anything about the axes. Just that rpm and tps are used as axes.


Bye

[kymi]

-ice-, nothing. Just tried to help you a bit.

[prj]

Don't have the ida project on this computer, but which 0x5D are you referring to?
Boost chip axis?