Frame Sync Options; Framed Versus Unframed - Analog Devices ADSP-BF506F Hardware Reference Manual

Frame Sync Options

Framing signals indicate the beginning of each serial word transfer. The
framing signals for each SPORT are TFS (transmit frame sync) and RFS
(receive frame sync). A variety of framing options are available; these
options are configured in the SPORT configuration registers
(SPORT_TCR1, SPORT_TCR2, SPORT_RCR1 and SPORT_RCR2).
The TFS and RFS signals of a SPORT are independent and are separately
configured in the control registers.

Framed Versus Unframed

The use of multiple frame sync signals is optional in SPORT communica-
tions. The TFSR (transmit frame sync required select) and RFSR (receive
frame sync required select) control bits determine whether frame sync sig-
nals are required. These bits are located in the SPORT_TCR1 and
SPORT_RCR1 registers.
When = 1 or
TFSR
word. To allow continuous transmitting by the SPORT, each new data
word must be loaded into the
word is shifted out and transmitted.
When = 0 or
TFSR
required. A single frame sync is needed to initiate communications but is
ignored after the first bit is transferred. Data words are then transferred
continuously, unframed.

With frame syncs not required, interrupt or DMA requests may
not be serviced frequently enough to guarantee continuous
unframed data flow. Monitor status bits or check for a SPORT
Error interrupt to detect underflow or overflow of data.
ADSP-BF50x Blackfin Processor Hardware Reference
= 1, a frame sync signal is required for every data
RFSR
SPORT_TX
= 0, the corresponding frame sync signal is not
RFSR
SPORT Controller
hold register before the previous
19-31