Thanks heaps for your research foxdie it's highly appreciated.
I wonder what the pin 53 A/T ECU input is. Is that the torque reduction request switch line or something fancier?
Thanks heaps for your research foxdie it's highly appreciated.
I wonder what the pin 53 A/T ECU input is. Is that the torque reduction request switch line or something fancier?
Also did you trace pin 60?
Pin 60 is front o2 heater sensor on the evo 6.. might be of interest given the input is still there.
doesn't look like there's likely to be more 5V inputs connected, theres certainly nothing on the evo 6 for comparison.
only hope would be to trace the pinout of the MCU itself and look for the analogue inputs i think?
Last edited by lathiat; 09-02-2012 at 05:15 PM.
There's more science to be done yet!
I started at the other end, the Hitachi H8/500 series CPU has 12 Analog inputs, each capable of reading 0-5V with 10-bit precision. I'm trying to match each one up to their respective ECU pin input to then determine if any are left over for use / abuse
After that, we should have a good idea (for the hardware side) if we can add more inputs, software however will be left to those with the tools to edit roms such as IDA Pro, this shouldn't be too difficult. Here's the list of all the ADC inputs and their addresses;
H8 ADC Ports ver 2.png
More info to come as it unravels
Last edited by foxdie; 09-02-2012 at 05:40 PM. Reason: Fixed table
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Yep I've been doing that for the last couple of hours
Unsure about pin 53, could be the torque reduction signal, but then didn't that just ease up the torque converter not engine power? Someone will confirm.
Pin 60... Nope, I've been waiting for someone to confirm its function, I'll take a look at that too.
So there is likely:
TPS, IAT, WATER TEMP, BAROMETER, VEHICLE SPEED, CAM PS, CRANK PS, MAF, KNOCK, LAMBDA1, LAMBDA2
I'm fairly sure those are all going to be analogue inputs - which is 11 total.. not sure what else there is or if any of those are not 5V analogue.
It would appear that basically all the analogue inputs are on that 1 connector, which would make sense I guess.
Last edited by lathiat; 09-02-2012 at 05:43 PM.
Although logical, I don't think thats true. Until I see direct proof, I'm not convinced that all those inputs are analog, given there's a total of 86 possible input pins on that CPU (76 digital input / output lines + 12 analog input lines).
TPS, IAT, Water Temp, Knock, Front Lambda and Rear Lambda will most likely be analog.
Barometer and MAF I'm not sure about, I believe that's a frequency input.
Cam PS, Crank PS and Vehicle Speed are hall effect sensors and will most likely be digital.
I'll update when I know more
The air flow from the MAF is definitely Hz, but I have no idea on the IAT and Barometer. I am pretty sure all those signals originate from the MAF though.
Sorry Trent, Pin 60 is a dead end too, missing components
Right, it's taking about 30 minutes per trace
AN0 = Coolant Temp Sensor
AN1 = Intake Air Temp Sensor
AN2 = Barometric Sensor
I guess all bets are off
Last edited by foxdie; 10-02-2012 at 12:16 AM. Reason: Correction
Sorry to ruin your parade
Here's what i've got from my notes. I'll be releasing a bunch more info about pins to use, etc once i can get my notes together into something that I can present.
AN0 = Coolant
AN1 = IAT
AN2 = Barometer
AN3 = Front O2 / Second Front O2 (input is multiplexed)
AN4 = Rear O2 / Second rear O2 (input is multiplexed)
AN5 = Battery
AN6 = Knock Sensor
AN7 = TPS
AN8 = fuel tank pressure - Unused on VR4
AN9 = Fuel level - unused on VR4
AN10 = Fuel temp - Unused on VR4
AN11 = MAP sensor - Unused on VR4
Cam Angle, Crank Angle, MAF, Speed, IFS all feed into H8's timer (pins are set as inputs for timers) as they are digital - H8 looks for either the rise or fall of a signal, generated an interupt that the ecu actions immediately (ie load next value into timer for injector time, coil dwell, change other I/O pins) - then resume back to the normal program loop
Airflow, vehicle speed timers are slightly different - it measures the time between pulses to determine these values - no action takes place in interupt, just update memort location with new value.
TIMER1 = Injectors
TIMER2 = Coils
Have fair idea on the other timers, but just confirming a few things before i release info.
I'd rather get my fact right before releasing info then let people discuss and prove it wrong, than for people to assume its correct.
Last edited by BCX; 10-02-2012 at 02:49 AM.
Ruin my parade will you eh?? *takes off his Stilettos* You're off my xmas card list now!
Just kidding I'm grateful you've saved me a lot of hassle, tracing lines with the naked eye has given me eyestrain.
Interesting about AN8-11, I'll focus my tracing on there to see if those can be repopulated
Have some rep
This is proving most difficult given the fact the traces for those pins go straight under the CPU. Anyone got any photos of a VR-4 7202 board with the CPU desoldered?
Run a continuity test between the pin and the point the track disappears.
please bear in mind, when you do a continutity/resistance test you put 2V (ish) into the circuit, this is how the meter calculates the resistance. so as long as the circut can take 2V you will be OK.
and by all reconing the inputs and outputs are 5V and 12V, even if there are 3v3 in's or out's you should still be OK.
Bye for Now!
Although your logic is sound, I only have a cheapo £10 multimeter from Maplin, it's got a 9V battery in there so I wouldn't put it past it to use 9V again for the continuity tester.
Chuck an LED across it to see how bright it glows with the continuity test.
Mine is an Anco cheapish multimeter, and I would estimate the voltage to be about 2v as it's quite dim.
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