Analog Devices Blackfin ADSP-BF537 Hardware Reference Manual page 736

Description of Operation
total channels. RX and TX must use the same 128-channel region to selec-
tively enable channels. The SPORT can do any of the following on each
channel:
• Transmit data
• Receive data
• Transmit and receive data
• Do nothing
Data companding and DMA transfers can also be used in multichannel
mode.
The pin is always driven (not three-stated) if the SPORT is enabled
DTPRI
( = in the
TSPEN 1
and an inactive time slot occurs. The
three-stated) if the SPORT is enabled and the secondary transmit is
enabled (
TXSE = 1
multichannel mode and an inactive time slot occurs.
The SPORT multichannel transmit select register and the SPORT
multichannel receive select register must be programmed before
enabling
mode. This is especially important in "DMA data unpacked
mode," since SPORT FIFO operation begins immediately after
and
RSPEN
(in
SPORTx_MCMC2
SPORTx_RX
nel operation, first disable
and
TXEN
TX or RX is not allowed.
12-16
register), unless it is in multichannel mode
SPORTx_TCR1
in the
SPORTx_TCR2
or
SPORTx_TX SPORTx_RX
are set, enabling both RX and TX. The
TSPEN
) must be enabled prior to enabling
operation. When disabling the SPORT from multichan-
TXEN
must be disabled before reenabling. Disabling only
RXEN
ADSP-BF537 Blackfin Processor Hardware Reference
pin is always driven (not
DTSEC
register), unless the SPORT is in
operation for multichannel
and then disable
bit
MCMEN
or
SPORTx_TX
. Note both
RXEN