6.11 TRF7970A Initialization
To properly initialize the TRF7970A, perform these steps:
- Raise the EN, EN2, and SS lines at the correct intervals after power up (for timing diagrams, see Figure 6-3 and Figure 6-4).
- Issue a Software Initialization direct command (0x03), followed by an Idle direct command (0x00) to soft reset the TRF7970A.
NOTE
Table 6-21 lists the initial register settings for the TRF7970A after the Software Initialization command.
- Delay 1 ms to allow the TRF7970A to fully process the soft reset.
- Issue a Reset FIFO direct command (0x0F).
- Write the Modulator and SYS_CLK Control register (0x09) with the appropriate application-specific setting for the crystal and system clock settings.
- (Optional) Write the Regulator and I/O Control register (0x0B) with the appropriate application-specific setting.
- Write the NFC Target Detection Level register (0x18) with the value of 0x00. For details on this requirement, see the TRF7970A Silicon Errata.