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Post Info TOPIC: hacking a teka


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hacking a teka


I don't have a teka, but I do have a suzuki
and I'd like to get some info about the teka
with the intention of emulating it if someone
can help me ...

specifically, if anyone has one how readily
can you connect +5v & 0v and also DMM
to the various pins and measure the voltages
you see at each setting of the teka?

also I'd like to find out for how long the teka
earths the 'write' line when a setting is entered

I'm kinda hoping that it's just a fancy processor-controlled
version of a yoshi box, but since it has more ranges on
it than the yoshi box, there has to be a little bit more to it

I'm also kinda hoping that the voltage levels it sets
line up with RR's observations from what the kawa ecu
is able to discern ... that'll mean that the code in the suz. ecu
is likely to be similar if not the same for reading the
three analog input lines

cheers,
MarkW


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I don't have any info on the Teka but I do have some on the Yosh Box.

Here is a schematic of a Yoshbox I got from a Suzuki TL site

Yoshbox schematic pdf

I also did a spread sheet to calculate the voltage for each voltage divider selection using the resistor values in the yosh box. Might save you a little time.

Yoshbox ratios pdf

I'm sure the Teka is just an embedded microcontroller with some D/A channels for the settings. Looking at the yosh box schematic I've always wondered why the idle mixture has a pot (infinetly adjustable) while the other mixture only allows +10, +5, 0, -5, -10. I wouldn't be suprised if you could use a pot on that mixture input too and if that is where the extra Teka settings come from.




-- Edited by RidgeRacer at 02:46, 2007-04-26

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yair, thanks RR, that's my thoughts as well

I've seen that yoshi schematic before, and have studied the user guide for the teka and it raises the following question: suppose you use a teka to adjust the fuel ratios in every range that the teka supports, and then at some later point in time you use the yoshi box to change the settings ... since the yoshi box doesn't have as many ranges to choose from, what happens to the settings that were made with the teka where the yoshi box doesn't have an equivalent (I'm talking about the throttle position settings here)?

would the resulting maps be a mix of the original teka settings and the later yoshi settings?

or does the ecu clear all the previous adjustments and start from scratch? - i.e. none of the original settings made with the teka would remain? - and if so what is the mechanism it uses to do this?

I need to understand these sorts of things before I launch into building something with too many options/settings ... I'm thinking along the lines that you mentioned above - a microprocessor with D/A on the three analog lines, with maybe a graphical LCD rather than a 16x2 LCD to display the configuration etc

of course my long term goal is to hack the ecu instead

cheers,
MarkW

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Of course I can't speak for the Denso software in the Suzukis but in the Kawasaki Denso code I looked at only the last setting is changed.

The only time it overwrites all the locations with default values is if during initialization after reset it finds two check bytes 0xAA,0x55 have been corrupted in the serial EEPROM chip where the EFI adjustment values are stored.

The way it works is there are 12 adjustment bytes, a hi, med, and low, for each cylinder in the serial EEPROM. At reset, if the EEPROM is not corrupted, these bytes are copied into RAM. When the bike is running the ECU calculates the injector duration using the map, air pressure, throttle etc. and then uses the RAM adjustment byte to offset plus or minus the injector value.

When the COS1 line is low the 8bit value of COV1 is written to one of the RAM adjustment byte determined by what cylinder / rpm is selected by COV2 and COV3 settings. This changes the real time setting of the ECU. If you turn off the bike and turn it back on at this point any changes are erased and replaced by those in the EEPROM as part of the reset initialization.

If you change an adjustment byte value and then hit the write button, COS2 Low, then that cylinder / rpm RAM byte is written to the EEPROM and will be the value used from now on to load the RAM when the ECU is reset.




In another thread the question was asked about the Write Low time needed to write a change into the ECU. The software I looked at has a debounce routine for COS1 and COS2 and a bit flag to show a change of status. The write need only be held low long enough to be debounced. The function that debounces the switches is part of the main housekeeping loop and called every pass or what I call one system tick. I don't know the time period that translates into yet but its not seconds. The injectors are update every 8th tick.

So lets see, engine redline is say 12000 rpm / 60secs = 200 rps; 1/200 = 5mS; 5mS / 8 = 0.625mS. A system tick has to be shorter than that. I'd start with 1mS and go from there.

Your mileage may vary.



-- Edited by RidgeRacer at 21:37, 2007-04-26

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According to the user manual the Teka has 10%,25%,50%,75% and 100% adjustment ranges.

I doubt that the Suzuki Denso ecu would have more than 3 x 4 maps as indicated in one of the other threads ? How is this 5 adjustment points made possible ?


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What did you want to measure from the TEKA ?

There is a PC based version of it sold in the UK too.

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I have a teka sitting in my shop somewhere tell me what you need and i will see what i can do.

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I have been using yoshbox for a couple of years now, but unfortunately as good as it is for optimizing the full rpm area - there is no way to adjust the part rpm & full throttle. That means that for max acceleration its completely useless device. After some mild modifications I soon got afr 11:1 with in 46rpm area for full throttle.

Anyeay having looked at the yoshbox signals from both inside yous box and inside ecu i am confident that generating a processor driven voltage outputting device is very easy. There is no magic in it...




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Besides seeing has how Bozo has hacked the SV1000 ECU I think he is probably not interested in the Teka anymore.

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yes, RR is right ... it took 6 months of waiting on ebay to get my ecu at the right price, and now my focus has shifted to the ECU - thanks for the offers though. Cheers, Mark.

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No problem i seen after i posted that this was a old post so i thought you might not need it no more but you never know.

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