Temperature not correct after updating firmware

I have a Melzi 2 from RP3d.com.
The board is approx 8 months old and was missing a lot od new feature including PID which is the main reason I upgraded.
After the upgrade my Temperature on both the extruder and hothead at room Temperature 20C are reading 39C
I have tried multiple Temperature sensor types but none go lower than approx 38C

I was lucky enought to receive the offical Marlin configs used withthis card and by reloading this firmware on the temperatures come right but diesnt' give me the new features.

I then had a look at the original Configuration.h and noticed it is using a custom temp table. I would suspect that if I could migrate this into the new firmware it would fix the issue but have no idea how.

As the sensor was part of a printer kit I have no idea what type was used for the bed and hot end.

I've included the original Configuration.h that works and has the custom temp table

Can I add a custom temp table and how?

thanks

So I've did some more digging on my board and seemed to be a Hybrid where it was a v1 board using a v2 microprocessor. This mean the bed and hot end resisters where likely to be 10K and not 4k7, which after checking this that was the issue. I replaced these and now the temperature is reading fine again how ever now I have another issue.

Upon start up the printer it auto sets the current head position as the home position, and the xyz axis won't decrease any lower, it will increase. Also if I increase it and then press a micro switch it does stop so it is using them, it just seems to be setting home straight away.

from your configuration .h

//// Endstop Settings
//#define ENDSTOPPULLUPS 1 // Comment this out (using // at the start of the line) to disable the endstop pullup resistors
// The pullups are needed if you directly connect a mechanical endswitch between the signal and ground pins.
const bool ENDSTOPS_INVERTING = true; //set to true to invert the logic of the endstops
//If your axes are only moving in one direction, make sure the endstops are connected properly.
//If your axes move in one direction ONLY when the endstops are triggered, set ENDSTOPS_INVERTING to true here

modify configuration .h

//// Endstop Settings
#define ENDSTOPPULLUPS 1 // Comment this out (using // at the start of the line) to disable the endstop pullup resistors
// The pullups are needed if you directly connect a mechanical endswitch between the signal and ground pins.
const bool ENDSTOPS_INVERTING = true; //set to true to invert the logic of the endstops
//If your axes are only moving in one direction, make sure the endstops are connected properly.
//If your axes move in one direction ONLY when the endstops are triggered, set ENDSTOPS_INVERTING to true here


usually with microswitches the endstop inverting is false unless the are normally closed switches.