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C164 Hardwareconfig. & crystal does not work well

Dear Sirs!
I work at my first "standalone_C164_tool"and got in trouble,could someone please check if I'm right with this Hardware (Pin)-configuration:

EA =high -for single chip mode (does Port0-levels takes effect on something?-At my board it's still doing for example on the clockconfig.!-I thought it should not.

NMI and RSTIN =high (I think otherwise there will be a permanent reset?)

That's all I have done -I think C164 works now out of the OTP with the clock frequency of the crystal .

The next big problem:
The crystal starts oscilating some seconds (20MHz)and than stops-or looks like random noise.
Because that I changed the capacitors from 12 to 20 pF (it changed nothing) I tried some resistors between XTAL2 and crystal (ca.120 Ohm) and some Resistors between the two pins of the crystal (100k to 600k).The current becomes extreme different values(between 70mA until 210mA with oscilating crystal-when it stoped oscilating the current sinks to 60-70 mA)

What could be wrong here?-the chip is good at the board,so it's not damaged.I tried different crystal with 5,10 MHz-that changed nothing.Perhaps the Port0 configuration isn't 'disabled'?

Is someone familiar with that? Please help me!
Thanks! hannes