ADS1292R: ADS1292 Lead-off detect abnormality

Part Number:ADS1292R

Hi:

   We have a device use the ADS1292 chip, we can read the ADC data correctly via the SPI bus when Lead wire is connected。

   But we found the lead-off detect is invalid when the lead wires is disconnected, the state of register is unchanged.  How can I get the correct state for lead-off detect？

   The state of status register read after lead wires connected or disconnected show below:

                                                            CH1                              CH2    

                                                         P        N                      P            N

  Lead wire disconnect                     0         1                      0             1

  Lead wire connect                          0         1                      0             1

                             0-->connected; 1-->disconnected.

      The ADS129's registers  configure as below：   

unsigned char ADS1292_Default_Register_Settings[12] = {
//Device ID read Ony
0x00,
//CONFIG1
0x02,
//CONFIG2
0xE0,
//LOFF
0x10,
//CH1SET (PGA gain = 6)
0x00,
//CH2SET (PGA gain = 6)
0x00,
//RLD_SENS (default)
0x20,
//LOFF_SENS (default)
0x3F, 
//LOFF_STAT
0x00,
//RESP1
0x02,
//RESP2
0x07,
//GPIO
0x0C 
};