CLK (R/X)
D(R/X)
FS(R/X)
A1
B7
B6
B5
B4
B3
B2
B1
B0
A0
C7
C6
C5
mcbsp-028
Public Version
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McBSP Functional Description
Table 21-17. Assumptions for the Single-Phase Frame Example
Assumption
Value
Bit or Field Name
Single-phase frame
‘0’
McBSPi.
[15] RPHASE bit
McBSPi.
[15] XPHASE bit
One word per frame
0x0
McBSPi.
[14:8] RFRLEN1 field
McBSPi.
[14:8] XFRLEN1 field
8-bit word length
0x0
McBSPi.
[7:5] RWDLEN1 field
McBSPi.
[7:5] XWDLEN1 field
word length in register2
ignored
McBSPi.
[14:8] RFRLEN2 field
McBSPi.
[14:8] XWDLEN2 field
Receive data clocked on falling edge
‘0’
McBSPi.
[0] CLKRP bit
Transmit data clocked on rising edge
McBSPi.
[1] CLKXP bit
Active–high frame–sync signals
‘0’
McBSPi.
[2] FSRP bit
McBSPi.
[3] FSXP bit
1-bit data delay
01b
McBSPi.
[1:0] RDATDLY field
McBSPi.
[1:0] XDARDLY field
Figure 21-29. Single-Phase Frame for a McBSP Data Transfer
21.4.2.4.3 Dual-Phase Frame Example
below shows an example of a frame. The first phase consists of one word of 16 bits,
followed by a second phase of one word of 8 bits. The entire bit stream in the frame is contiguous. There
are no gaps between words/phases.
shows the assumptions used to the example in
.
Table 21-18. Assumptions for the Dual-Phase Frame Example
Assumption
Value
Bit or Field name
Single-phase frame
‘1’
McBSPi.
[15] RPHASE bit
McBSPi.
[15] XPHASE bit
One word per frame
0x0
McBSPi.
[14:8] RFRLEN1 field
McBSPi.
[14:8] XFRLEN1 field
16-bit word length
0x0
McBSPi.
[7:5] RWDLEN1 field
McBSPi.
[7:5] XWDLEN1 field
8-bit word length
0x2
McBSPi.
[14:8] RFRLEN2 field
McBSPi.
[14:8] XWDLEN2 field
Receive data clocked on falling edge
‘0’
McBSPi.
[0] CLKRP bit
Transmit data clocked on rising edge
McBSPi.
[1] CLKXP bit
Active-high frame-sync signals
‘0’
McBSPi.
[2] FSRP bit
McBSPi.
[3] FSXP bit
0-bit data delay
00b
McBSPi.
[1:0] RDATDLY field
McBSPi.
[1:0] XDARDLY field
3099
SWPU177N – December 2009 – Revised November 2010
Multi-Channel Buffered Serial Port
Copyright © 2009–2010, Texas Instruments Incorporated