Hi all,
I am trying to edit the lookup tables to get the '7727 to use a Toyota CTS which is close, but towards the higher temps, the resistances are off enough to throw off the ADC counts alot. 212*F water reads right around 240*F on ADX.
So, in my quest to understand the dual tables, and see if I can actually do the A/D count math close enough to hand tweak, I looked at the following drawing from Ludis's schematics.
There is a "348 ohm" table and a "4k ohm" table in the $8D disassemblies... What is weird is the diagram from Ludis. I am NOT an EE and maybe I just don't get what is going on, but it looks to me that this diagram has the two resistors (348 ohm and 3.65k ohm) backwards?
If not, how does the 348 ohm pull up actually occur? It seems like it would be a 3.65k ohm pull up for CTSHI, or a 4k ohm pull up for CTS?
Last question: If I have some temp/resistance numbers for the toyota sensor, how do I back into the AD Counts to populate the table.
Thanks for the help and advice...
-Brett
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