On frdm-kl46z board I am trying to do jtag acces to K20DX128 via connector J14 "OpenSDA INTERFACE JTAG CONNECTOR".
I can read IDCODE when K20DX128 is kept under reset with SDA_RST_B signal is low.
When K20DX128 is powered up TDO is all zero.
Is IDCODE can only be read under reset state?
Note: K20DX128 runs https://github.com/ARMmbed/DAPLink/blob/main/source/hic_hal/freescale/k20dx/gcc/startup_MK20D5.S and in main only an empty while loop
