4 register description – Rainbow Electronics AT86RF231 User Manual
Page 103
103
8111A–AVR–05/08
AT86RF231
9.1.4
Register Description
Register 0x15 (RX_SYN):
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
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-
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
7
6
5
4
3
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
0
0
0
0
0
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