I searched and didnt really see anything here, is it different installing the 3.57 board in an rx-7 VS the 3.0?

 

The main difference is that a lot of the mods you have to do to a v3 board are not necessary on the 3.57 board. For example, the 3.57 has built-in pullup resistors on the LEDs for ignition.

You still have to switch the MAT sensor bias resistor, which can be tough with the SMT board (instead of using through-holes).

Also, you will still need a second VR signal conditioner if you choose to run a stock CAS.

Ken

 

So, out of the fact that we will need to mod it still, i should stick to the version 3 board then, or is there someone else who could handle these mods, because we're sticking with the stock CAS.

 

Ken, I'm sort of curious now. When running MSII is it still necessary to change the resistor? I noticed that the thermistor table calibration allows you to define the bias resistor. Originally when I built my MS I calibrated the table using the "stock" bias resistor and the S4 TII air temp sensor. The sensor seemed to be accurate, but I switched to the suggested resistor in the FAQ and re calibrated the tables. Both configurations seemed to report the same temperatures in the same manner.

Is the bias resistor just an MS1 thing, or is it absolutely necessary in MSII as well?

 

I dare say it is a case of getting the most temperature resolution from the ADC. Temperature reading is done by measuring the voltage across the resistor with respect to the voltage drop across the thermistor.

Look at the circuit schematic and draw up the voltage divider and see what happens if you use a value larger or smaller than the suggested.

 

Jobro has it right.

You can have it work with just about any resistor value, but you won't be making full use of the 0-5v range of the ADC input unless you use the recommended resistor value.

It just won't be as accurate. This will be less noticable on the ms2 since it has 10-bit ADC ports instead of 8-bit (1024 levels instead of 255). It'll be more accurate even if you're not using the full range than the ms1 would be using the full range.

Ken