AT86RF401E ATMEL [ATMEL Corporation], AT86RF401E Datasheet - Page 30

• Manufacturer Part Number: AT86RF401E
• Description: Smart RF Wireless Data Microtransmitter
• Manufacturer: ATMEL [ATMEL Corporation]

Transmit Control Register – TX_CNTL
Power Attenuation Control Register – PWR_ATTEN
30
Initial Value
Initial Value
Read/Write
Read/Write
AT86RF401
$12
$14
Bit
Bit
R/W
R/W
7
–
0
7
–
0
• Bit[7:6]
Reserved.
• Bit[5]: TXE, Transmitter Enable
This bit, when set, turns on the phase locked loop (PLL) RF frequency synthesizer but
should not be used to modulate the RF carrier or excessive spurious noise may result.
• Bit[4]: TXK, Transmitter Key
This bit, when set, turns on the RF power amplifier. It should be used to modulate the
RF carrier manually. This bit should be cleared when the bit timer is configured in trans-
mit mode.
Figure 25. Modulation Control Logic
• Bit[3]
Reserved.
• Bit[2]: LOC, PLL Lock
This bit is set when the frequency synthesizer in the transmitter is locked. Typically, the
programmer should test the status of this bit to insure the RF carrier is stable prior to
turning on the RF power amplifier.
This register is used to select the power attenuation level. The total power attenuation is
the sum of the coarse attenuation and fine attenuation. As an example, to obtain 15 dB
of attenuation, the coarse setting of 12 dB and fine setting of 3 dB would be selected. To
obtain 12 dB coarse attenuation, Bits[5:3] would be set to [010]. To obtain 3 dB of fine
attentuation would require Bits[2:0] to be set to [011].
Note:
• Bits[7:6]
Reserved
R/W
R/W
6
–
0
6
–
0
Maximum RF output power occurs when Bits[5:0] = [000000].
Bit Timer
PCC2
TXK
R/W
TXE
R/W
5
0
5
0
PCC1
R/W
TXK
R/W
4
0
4
0
PCC0
R/W
R/W
3
–
0
3
0
PLL
PCF2
LOC
R/W
R
2
0
2
0
RF
IN
POWER
ON/OFF
AMP
PCF1
R/W
R/W
1
0
1
–
0
OUT
RF
1424F–RKE–12/03
PCF0
R/W
R/W
0
0
0
–
0