MRF49XAT-I-ST Datasheet, PDF (32/102 Pages) Microchip Technology – ISM Band Sub-GHz RF Transceiver

MRF49XA
REGISTER 2-10: FIFORSTREG: FIFO AND RESET MODE CONFIGURATION REGISTER
(POR: 0xCA80)
W-1
W-1
W-0
W-0
W-1
W-0
W-1
W-0
CCB<15:8>
bit 15
bit 8
W-1
bit 7
W-0
W-0
FFBC<3:0>
W-0
W-0
W-0
SYCHLEN
FFSC
W-0
FSCF
W-0
DRSTM
bit 0
Legend:
R = Readable bit
-n = Value at POR
r = reserved bit
W = Writable bit
‘1’ = Bit is set
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-8
bit 7-4
bit 3
bit 2
bit 1
bit 0
CCB<15:8>: Command Code bits
The command code bits (11001010b) are serially sent to the microcontroller to identify the bits to be
written in the FIFORSTREG.
FFBC<3:0>: FIFO Fill Bit Count bits
Sets the received bits before generating an external interrupt to the host microcontroller to indicate the
receive FIFO is ready to be read. The maximum fill level is 15⁽¹⁾.
SYCHLEN: Synchronous Character Length bit
This bit sets the synchronous character length to byte or word long.⁽²⁾
1 = Byte long. User-programmable SCL0 byte is used.
0 = Word long. The character is composed of the SCL1 and SCL0 bytes. The SCL1 byte value is fixed
and is not configurable. The SCL0 byte value is user-programmable through the SYNBREG.
FFSC: FIFO Fill Start Condition bit
This bit sets the condition at which the FIFO starts filling with data.
1 = The FIFO will continuously fill irrespective of noise or good data
0 = The FIFO will fill when it recognizes the synchronous character pattern as defined internally
FSCF: FIFO Synchronous Character Fill bit
1 = The FIFO starts filling with data when it detects the synchronous character pattern as defined in
the FFSC bit
0 = The FIFO fill stops
To restart the synchronous character pattern recognition, just clear and set this bit⁽²⁾.
DRSTM: Disable (Sensitive) Reset mode bit
1 = Disables⁽³⁾
0 = Enables System Reset for any glitches above 0.2V in the power supply
Note 1:
2:
3:
On register overrun, the data will be lost. Therefore, the developer must take into account the processing
time required to read-out data before a register overrun. It is recommended to set the fill value to half of
the desired number of bits to be read to ensure sufficient time for additional processing. See Register 2-1
for the description of the TXRXFIFO and TXUROW bits, and Register 2-9 for details on polling and
interrupt driven FIFO reads from the SPI bus.
For synchronous character length selection, see Table 2-8.
For Reset mode selection, see Table 2-9.
DS70590C-page 32
Preliminary
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