User Manual

103

8111A–AVR–05/08

AT86RF231

9.1.4 Register Description

This register controls the sensitivity threshold of the receiver.

• Bit 7 - RX_PDT_DIS

RX_PDT_DIS = 1 prevents the reception of a frame even if the radio transceiver is in receive

modes. An ongoing frame reception is not affected. This operation mode is independent of the

setting of register bits RX_PDT_LEVEL.

• Bit [6:4] - Reserved

• Bit [3:0] - RX_ PDT_LEVEL

These register bits desensitize the receiver such that frames with an RSSI level below the

RX_PDT_LEVEL threshold level (if RX_PDT_LEVEL > 0) are not received. The threshold level

can be calculated according to the following formula:

RX_THRES = RSSI_BASE_VAL + 3 * (RX_PDT_LEVEL -1), for RX_PDT_LEVEL > 0

Examples for certain register settings are given in Table 9-1 on page 103

If register bits RX_PDT_LEVEL > 0 the current consumption of the receiver in states RX_ON

and RX_AACK_ON is reduced by 500 µA, refer to Section 12.8 “Current Consumption Specifi-

cations” on page 161 parameter 12.8.3.

If register bits RX_PDT_LEVEL = 0 (reset value) all frames with a valid SHR and PHR are

received, independently of their signal strength.

Bit 76 543 2 1 0

+0x15 RX_PDT_DIS Reserved RX_PDT_LEVEL RX_SYN

Read/Write R/W R R R R/W R/W R/W R/W

Reset Value 00 000 0 0 0

Table 9-1. Receiver Desensitization Threshold Level - RX_PDT_LEVEL

Value [Register] RX Input Threshold Level Value [dBm]

0x0

<= RSSI_BASE_VAL (reset value) RSSI value not considered

0x1 > RSSI_BASE_VAL + 0 * 3 > -90

...

0xE > RSSI_BASE_VAL + 13 * 3 > -51

0xF > RSSI_BASE_VAL + 14 * 3 > -48