Well, you are polling for the ADC to finish, I don't believe you need to call ADC_StopConvert(); afterwards, as it only returns if it completed the ADC conversion. That might be why it is causing randoms values to spit out?
Just as an FYI, Modulus operations (% symbol) are very slow in programs, so if you want better performance/speeds, trying not to use it is preferable.
Try debugging the program with the SWD ports, and see what values the RAM are showing for iTemp, iRes, and how the filtering.
Since I could not figure out your top circuit, I'll put my temp test project (for CY8CKIT-044).
May be you need to recreate the project for -042.
My top circuit is
And as "B" parameter of my therm is different from yours,
please modify line 24 of main.c from
#define B 3435
#define B 3492
And as I'm using log(), we need to add command line "-lm" in Build Settings Compiler and Linker
Hope this can be a bit of hint/help.
Your project seems to be working fine. Can you please check the following?
1. See if the bias voltage is applied
2. Check the connection from P4 on header J3 to PSoC 5LP's P12 on header J8 for UART
Also, please check if you can make a change in firmware as suggested by other members.