[106] RADIO: Higher CRC error rates for some access addresses

This anomaly applies to Revision 1, build codes QFAA-Bx0, CIAA-Bx0, QFAB-Bx0.

It was inherited from the previous IC revision Engineering C.

Symptoms

Payload in RX is corrupted.

Conditions

BLE and Nordic proprietary radio mode. 4 and 5 byte addresses. 1 in 1600 (<0.07%) randomly generated BLE addresses and 1 in 1200 (<0.09%) randomly generated proprietary addresses are affected.

Consequences

The radio reports up to 30% CRC error rate for packets being received when affected access addresses are used. For BLE, new access addresses are generated on each connection so the symptom is rare and not persistent.

Workaround

Use one of the following workarounds:
  • Use SoftDevice s132_nrf52_4.0.2 or later and the ESB and Gazell libraries of SDK v14.0.0 or later to avoid higher CRC error rate.

    The S132 SoftDevice detects when affected access addresses are being used in a connection and applies the following workaround resulting in 3 dB reduced sensitivity for approximately 0.1% of connections. The ESB and Gazell libraries apply the following workaround for all addresses.

  • Apply the following code before triggering the RXEN task:
    
     *(volatile uint32_t *) 0x40001774 = ((*(volatile uint32_t *) 0x40001774) & 0xfffffffe) | 0x01000000;
    
    This code will reduce sensitivity with 3 dB.