ADSP-BF535 Blackfin Processor Hardware Reference
11-67
Serial Port Controllers
Setting the
MCM
bit enables multichannel operation for
both
the receive and
transmit sides of the SPORT. Therefore, if a receiving SPORT is in multi-
channel mode, the transmitting SPORT must also be in multichannel
mode.
Multichannel DMA Data Packing
Multichannel DMA data packing and unpacking are specified with the
MCDTXPE
and
MCDRXPE
bits in the
SPORTx_MCMC2
multichannel configuration
registers.
If the bits are set, indicating that data is packed, the SPORT expects that
the data contained by the DMA buffer corresponds only to the enabled
SPORT channels. For example, if an MCM frame contains 10 enabled
channels, the SPORT expects the DMA buffer to contain 10 consecutive
words for each of the frames. It is not possible to change the total number
of enabled channels without changing the DMA buffer size, and reconfig-
uring is not allowed while the SPORT is enabled.
If the bits are cleared (the default, indicating that data is not packed), the
SPORT expects the DMA buffer to have a word for each of the channels
in the window, whether enabled or not, so the DMA buffer size must be
equal to the size of the window. For example, if channels 1 and 10 are
enabled, and the window size is 16, the DMA buffer size would have to be
16 words. The data to be transmitted or received would be placed at
addresses 1 and 10 of the buffer, and the rest of the words in the DMA
buffer would be ignored. This mode has no restrictions on changing the
number of enabled channels while the SPORT is enabled.
Summary of Contents for ADSP-BF535 Blackfin
Page 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Page 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Page 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Page 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Page 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Page 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Page 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Page 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Page 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Page 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Page 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...