RepRap Host Temperature differences

I just updated my RepRap host software/firmware. Now I'm getting strange results from the temp setting when I turn on the heater. I made sure I'm using the same thermistor settings as before but I'm getting different behavior. Things look good up until my temp reaches 255. Then it jumps way up to to 289 and eventually reads 322 or something in that neighborhood. I don't believe it is anywhere near that hot because the end is not drooling near as much as it did before with temps around 240 - 250. Before, when I set it on 259 or above it started smoking, stinking and burning the ABS. Not I'm barely getting anything out of it. My thermistor is from Makerbot and here is the table I'm using in both the motherboard and extruder board firmware.

#define NUMTEMPS 20
short temptable[NUMTEMPS][2] = {
{1, 841},
{54, 255},
{107, 209},
{160, 184},
{213, 166},
{266, 153},
{319, 142},
{372, 132},
{425, 124},
{478, 116},
{531, 108},
{584, 101},
{637, 93},
{690, 86},
{743, 78},
{796, 70},
{849, 61},
{902, 50},
{955, 34},
{1008, 3}
};

Am I using the right table? I looked it up but I may still have gotten it wrong. Anyone have any ideas? Do I need to do anything in the firmware besides setting the table? It looked like the USE_THERMISTOR was NOT defined for motherboard = 2 in the motherboard firmware. I'm using 5D boards. Do I need to define that so the table is created on the motherboard?

Can anyone help out here?

If I understand it correctly, you only need temperature.h on the extruder controller, as it controls the temperature and sends the readings back to the mb.
I had the same problem when I updated my firmware. I believe it must have been from me forgetting to save the correct file or something. I'm sure you did, but double check that you really have the proper temperature.h, and that it uploaded correctly. Also make sure you didn't forget to comment out the other thermistor tables.

You can also try to roll back to the previous firmware and see if the problem persist. If it does, perhaps the thermistor might have loosened a bit, and now have a bad thermal connection? Try to take the thermistor off and measure how accurate it measure boiling water.

Good luck!

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-Nudel
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