Multichannel Selection Modes
1070
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
C28 Multichannel Buffered Serial Port (McBSP)
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XWDLEN1 = 000b: 8 bits per word
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XMCME = 0: 2-partition mode (only partitions A and B used)
In the case where XMCM = 11b, transmission and reception are symmetric, which means the
corresponding bits for the receiver (RPHASE, RFRLEN1, RWDLEN1, and RMCME) must have the same
values as XPHASE, XFRLEN1, and XWDLEN1, respectively.
In the figure, the arrows showing where the various events occur are only sample indications. Wherever
possible, there is a time window in which these events can occur.
15.6.7.3 Using Interrupts Between Block Transfers
When a multichannel selection mode is used, an interrupt request can be sent to the CPU at the end of
every 16-channel block (at the boundary between partitions and at the end of the frame). In the receive
multichannel selection mode, a receive interrupt (RINT) request is generated at the end of each block
transfer if RINTM = 01b. In any of the transmit multichannel selection modes, a transmit interrupt (XINT)
request is generated at the end of each block transfer if XINTM = 01b. When RINTM/XINTM = 01b, no
interrupt is generated unless a multichannel selection mode is on.
These interrupt pulses are active high and last for two CPU clock cycles.
This type of interrupt is especially helpful if you are using the two-partition mode (described in
) and you want to know when you can assign a different block of channels to partition A or
B.