TRF7970A: default init TRF7970A

Hi.

I'm using the TRF7970A in SPI and I'm having a problem with some component.

After a power down the initialization of the TRF fails and no tag reading is possible

you have to turn off the power for more than 2 seconds and at power on initialization works.

EN is driven by the μc EN2 is connected to VSS

My init sequence:

Power on

EN = 0 ;

Delay 100ms    

 EN  = 1;

delayEnMs(20) ;              // wait tempo 20ms until system clock started

mod_control[0] = SOFT_INIT;             // 0x03

SpiTrf797xDirectCommand(mod_control);  

mod_control[0] = IDLE;                 // 0x00

SpiTrf797xDirectCommand(mod_control);

mod_control[0] = MODULATOR_CONTROL;     // 0x09

mod_control[1] = 0x09;                                                               // OOK 100%, ASK/OOK as an analog output

SpiTrf797xWriteSingle(mod_control, 2);

mod_control[0] = MODULATOR_CONTROL;

SpiTrf797xReadSingle(mod_control, 1);

 if (mod_control[0] != mod_control[1])

 {

     // defaut init

     res = 0;

}

Can you help me