Table 15-81. XCR2 Register Field Descriptions (continued)
Bit
Field
Type
Reset
Description
7-5
XWDLEN2
R/W
0h
Transmit word length 2.
Each frame of transmit data can have one or two phases, depending
on the value that you load into the XPHASE bit. If a single-phase
frame is selected, XWDLEN1 in XCR1 selects the length for every
serial word transmitted in the frame. If a dual-phase frame is
selected, XWDLEN1 determines the length of the serial words in
phase 1 of the frame and XWDLEN2 in XCR2 determines the word
length in phase 2 of the frame.
Reset type: SYSRSn
0h (R/W) = 8 bits
1h (R/W) = 12 bits
2h (R/W) = 16 bits
3h (R/W) = 20 bits
4h (R/W) = 24 bits
5h (R/W) = 32 bits
6h (R/W) = Reserved (do not use)
7h (R/W) = Reserved (do not use)
4-3
XCOMPAND
R/W
0h
Transmit companding mode bits.
Companding (COMpress and exPAND) hardware allows
compression and expansion of data in either μ-law or A-law format.
Reset type: SYSRSn
0h (R/W) = No companding, any size data, MSB received first
1h (R/W) = No companding, 8-bit data, LSB received first
2h (R/W) = u-law companding, 8-bit data, MSB received first
3h (R/W) = A-law companding, 8-bit data, MSB received first
2
XFIG
R/W
0h
Transmit frame-synchronization ignore bit.
If a frame-synchronization pulse starts the transfer of a new frame
before the current frame is fully transmitted, this pulse is treated as
an unexpected frame-synchronization pulse.
Setting XFIG causes the serial port to ignore unexpected frame-
synchronization pulses during transmission.
Reset type: SYSRSn
0h (R/W) = Frame-synchronization detect. An unexpected FSX pulse
causes the transmitter to discard the content of XSR[1,2]. The
transmitter:
1. Aborts the present transmission
2. Sets XSYNCERR in SPCR2
3. Begins a new transmission from DXR[1,2]. If new data was written
to DXR[1,2] since the last DXR[1,2]-to-XSR[1,2] copy, the current
value in XSR[1,2] is lost. Otherwise, the same data is transmitted.
1h (R/W) = Frame-synchronization ignore. An unexpected FSX pulse
is ignored. Transmission continues uninterrupted.
1-0
XDATDLY
R/W
0h
Transmit data delay bits. XDATDLY specifies a data delay of 0, 1,
or 2 transmit clock cycles after frame synchronization and before the
transmission of the first bit of the frame.
Reset type: SYSRSn
0h (R/W) = 0-bit data delay
1h (R/W) = 1-bit data delay
2h (R/W) = 2-bit data delay
3h (R/W) = Reserved (do not use)
Multichannel Buffered Serial Port (McBSP)
SPRUH18I – JANUARY 2011 – REVISED JUNE 2022
TMS320x2806x Microcontrollers
973
Copyright © 2022 Texas Instruments Incorporated
Содержание TMS320 2806 Series
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