McBSP Registers
1143
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
C28 Multichannel Buffered Serial Port (McBSP)
15.12.11.1 XCERs Used in a Transmit Multichannel Selection Mode
For multichannel selection operation, the assignment of channels to the XCERs depends on whether 32 or
128 channels are individually selectable, as defined by the XMCME bit. These two cases are shown in
. The table shows which block of channels is assigned to each XCER that is used. For each
XCER, the table shows which channel is assigned to each of the bits.
NOTE:
When XMCM = 11b (for symmetric transmission and reception), the transmitter uses the
receive channel enable registers (RCERs) to enable channels and uses the XCERs to
unmask channels for transmission.
Table 15-91. Use of the Transmit Channel Enable Registers
Number of
Selectable
Channels
Block Assignments
Channel Assignments
XCERx
Block Assigned
Bit in XCERx
Channel Assigned
32
(XMCME = 0)
XCERA
Channels n to (n + 15)
XCE0
Channel n
XCE1
Channel (n + 1)
XCE2
Channel (n + 2)
:
:
When XMCM = 01b or 10b, the block
of channels is chosen with the
XPABLK bits. When XMCM = 11b,
the block is chosen with the RPABLK
bits.
XCE15
Channel (n + 15)
XCERB
Channels m to (m + 15)
XCE0
Channel m
XCE1
Channel (m + 1)
XCE2
Channel (m + 2)
:
:
When XMCM = 01b or 10b, the block
of channels is chosen with the
XPBBLK bits. When XMCM = 11b,
the block is chosen with the RPBBLK
bits.
XCE15
Channel (m + 15)
128
(XMCME = 1)
XCERA
Block 0
XCE0
Channel 0
XCE1
Channel 1
XCE2
Channel 2
:
:
XCE15
Channel 15
XCERB
Block 1
XCE0
Channel 16
XCE1
Channel 17
XCE2
Channel 18
:
:
XCE15
Channel 31
XCERC
Block 2
XCE0
Channel 32
XCE1
Channel 33
XCE2
Channel 34
:
:
XCE15
Channel 47
XCERD
Block 3
XCE0
Channel 48
XCE1
Channel 49
XCE2
Channel 50
:
:
XCE15
Channel 63