NXP Semiconductors FXTH870 D Series, Руководство пользователя

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FXTH870xD
Sensors
Freescale Semiconductor, Inc.
127
13.15 RFM Control Register 6 - RFCR6
The RFCR6 register contains eight control bits to set the initial and interframe frame number timing variable as described in
Figure 105 . A RFMRST signal clears the RFFT[5:0] bits.
13.16 RFM Control Register 7 - RFCR7
The RFCR7 register contains four control bits and four status bits for the RFM as described in Figure 106 .
$0036 Bit 7 6 5 4 3 2 1 Bit 0
R
VCO_GAIN[1:0] RFFT[5:0}
W
RFMRST:
1 0 0 0 0 0 0 0
Figure 105. RFCR6 Register - Frame Number Time - RFTS[1:0] = 1:0
Table 80. RFCR6 Field Descriptions
Field Description
7:6
VCO_GAIN
[1:0]
VCO Gain Selection - These bits control the VCO gain. The VCO_GAIN[1] bit is set and the VCO_GAIN[0] bit is cleared by the
RFMRST signal. Not normally need to be adjusted by the end user.
5:0
RFFT[5:0]
Frame Number Timer - The RFFT[5:0] control bits select the interframe timing between multiple frames of transmission. The
time value is equal to a nominal one millisecond for each count of the RFFT[5:0] bits multiplied by the frame number of the last
transmitted frame. The RFFT[5:0] control bits are cleared by the RFMRST signal.
$0037 Bit 7 6 5 4 3 2 1 Bit 0
R
RFIF RFEF RFVF 0
RFIEN RFLVDEN RCTS
0
W
RFIAK RFMRST
RFMRST:
0 0 0 0 0 0 0 0
= Reserved
Figure 106. RFM Transmit Control Registers (RFCR7)
Table 81. RFCR7 Field Descriptions
Field Description
7
RFIF
RF Interrupt Flag — The read-only RFIF status bit indicates if the RF transmission has ended properly when using the data buffer
mode and the SEND bit has been cleared. Writes to this bit will be ignored. The RFIF status bit is cleared by writing a logical one
to the RFIAK bit or the RFMRST bit. RFMRST signal clears this bit.
0
RF transmission in progress or not in the data buffer mode.
1 RF transmission completed in the data buffer mode.
6
RFEF
RF Transmission Error Flag — The read-only RFEF status bit indicates if there was an error in the current or prior RF
transmission as described in Section 13.6.4 . Writes to this bit will be ignored. The RFEF status bit is cleared by writing a logical
one to the RFIAK bit or the RFMRST bit. RFMRST signal clears this bit.
0
No RF transmission error occurred.
1 RF transmission error occurred.
5
RFVF
RF LVD Trigger Flag — When the RF LVD is enabled and the supply voltage falls below the threshold, the read-only RFVF flag
will be set if the RFLVDEN bit is set. Writes to this bit will be ignored. The RFVF status bit is cleared by writing a logical one to
the RFIAK bit or the RFMRST bit. RFMRST signal clears this bit
0
Voltage is and has been above RF LVD rising threshold or the RF LVD is disabled.
1 Voltage has dropped below the RF LVD falling threshold since last reset of this bit.
4
RFIAK
Acknowledge RF Interrupt Flags — Writing a one to the RFIAK bit clears the RFIF, RFEF and RFVF flag bits. Writing a zero to
the RFIAK bit has no effect on the RFIF, RFEF and RFVF flag bits. The RFMRST signal has no effect on this bit.
0
No effect.
1 Clear the RFIF, RFEF, and RFVF bits.