1. I can read the configuration data "F0 00 00 00 00 00".
The configuration data is modified by setting for example REFON=1, checking DCC bits for activation, or selecting OV/UV settings. The default write may have been successful even though not matching the first byte on readback, since some of the bits are GPIO read/write and might not match whats written due to the open-drain pins of the IC. Also the GUI will not keep the part awake unless REFON=1 and written, so subsequent reads could show that the register was cleared automatically after the watchdog timeout (~1.5s).
Thank you for your answer. As you said, the configuration register will be reset if there are no new instructions in 2 seconds.
How can I modify the high and low level state of GPIO in software, especially GPIO , GPIO , GPIO ?
Because these pins are used for temperature acquisition channel switching in DEMO board DC1942C.