Texas Instruments TLV1562 - Manual (Page 17)

Other DSP/TLV1562 Signals
11 Interfacing the TLV1562 Parallel ADC to the TMS320C54x DSP
6 Other DSP/TLV1562 Signals
These paragraphs describe other DSP and TLV1562 signals.
6.1 DSP Internal Serial Port Operation
Three signals are necessary to connect the transmit pins of the transmitting
device with the receive pins of the receiving device for data transmission. The
transmitted serial data signal (BDX) sends the actual data. BFSX initiates the
transfer (at the beginning of the packet), and BCLKX clocks the bit transfer. The
corresponding pins on the receive device are BDR, BFSR and BCLKR,
respectively.
The transmit is executed by the autobuffer mode. This means there is no need
to write to the serial port output buffer. Instead, the DSP continuously sends the
data, located in the memory beginning on AXR. When all data are sent (defined
by the buffer length in BXR), the first word (pointed to by AXR) is sent again.
Therefore, the program has only to store the samples into this memory location.
The rest of the task is handled in the background, using no CPU power.