ATmega1284PR231 Atmel Corporation, ATmega1284PR231 Datasheet - Page 144

• Manufacturer Part Number: ATmega1284PR231
• Manufacturer: Atmel Corporation

Specifications of ATmega1284PR231

• Flash (kbytes): 128 Kbytes
• Max. Operating Frequency: 20 MHz
• Max I/o Pins: 32
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Crypto Engine: AES
• Sram (kbytes): 16
• Eeprom (bytes): 4096
• Operating Voltage (vcc): 1.8 to 3.6
• Timers: 3
• Frequency Band: 2.4 GHz
• Max Data Rate (mb/s): 2
• Antenna Diversity: Yes
• External Pa Control: Yes
• Power Output (dbm): 3
• Receiver Sensitivity (dbm): -101
• Receive Current Consumption (ma): 13.2
• Transmit Current Consumption (ma): 14.4
• Link Budget (dbm): 104

8111C–MCU Wireless–09/09
Bit
+0x0D
Read/Write
Reset Value
ANT_SEL
7
R
0
• Bit [3:0] - PDT_THRES
These register bits control the sensitivity of the receiver correlation unit. If the Antenna Diversity
algorithm is enabled (ANT_DIV_EN = 1), the value shall be set to PDT_THRES = 3, otherwise it
shall be set back to the reset value. This is not automatically done by the hardware.
Table 11-10. Receiver Sensitivity Control
Register 0x0D (ANT_DIV):
The ANT_DIV register controls Antenna Diversity.
• Bit 7 - ANT_SEL
This register bit signals the currently selected antenna path. The selection may be based either
on the last antenna diversity cycle (ANT_DIV_EN = 1) or on the content of register bits
ANT_CTRL, for details refer to
142.
Table 11-11. Antenna Diversity - Antenna Status
• Bit [6:4] - Reserved
• Bit 3 - ANT_DIV_EN
If register bit ANT_DIV_EN is set, the Antenna Diversity algorithm is enabled. On reception of a
frame the algorithm selects an antenna autonomously during SHR search. This selection is kept
until:
Register Bit
PDT_THRES
Register Bit
ANT_SEL
• A new SHR search starts
• Leaving receive states
• Manually programmed register bits ANT_CTRL
6
R
0
Reserved
5
R
0
Value
Other
Value
0x7
0x3
0
1
4
R
0
Description
Reset value, to be used if Antenna Diversity algorithm is disabled
Recommended correlator threshold for Antenna Diversity operation
Reserved
Description
Antenna 0
Antenna 1
Section 11.4.2 “Antenna Diversity Application Example” on page
ANT_DIV_EN
R/W
3
0
ANT_EXT_SW_EN
R/W
2
0
R/W
1
1
ANT_CTRL
AT86RF231
R/W
0
1
ANT_DIV
144