Datasheet

AD5370
Rev. 0 | Page 26 of 28
INTERFACING EXAMPLES
The Analog Devices ADSP-21065L is a floating point DSP with
two serial ports (SPORTs).
Figure 24 shows how one SPORT
can be used to control the AD5370. In this example, the transmit
frame synchronization (TFS) pin is connected to the receive
frame synchronization (RFS) pin. The transmit and receive
clocks (TCLK and RCLK) are also connected together. The user
can write to the AD5370 by writing to the transmit register. A read
operation can be accomplished by first writing to the AD5370
to tell the part that a read operation is required. A second write
operation with an NOP instruction causes the data to be read
from the AD5370. The DSP receive interrupt can be used to
indicate when the read operation is complete.
The SPI interface of the AD5370 is designed to allow the parts to be
easily connected to industry-standard DSPs and microcontrollers.
Figure 23 shows how the AD5370 can be connected to the
Analog Devices, Inc., Blackfin® DSP. The Blackfin has an integrated
SPI port that can be connected directly to the SPI pins of the
AD5370, as well as programmable input/output pins that can be
used to set or read the state of the digital input or output pins
associated with the interface.
SPISELx
ADSP-BF531
AD5370
SCK
MOSI
MISO
PF10
PF8
PF9
PF7
SYNC
SCLK
SDI
SDO
RESET
CLR
LDAC
BUSY
05813-023
SYNC
SCLK
SDI
SDO
RESET
CLR
LDAC
BUSY
AD5370 ADSP-21065L
TFSx
RFSx
TCLKx
RCLKx
DTxA
DRxA
FLAG
0
FLAG
1
FLAG
2
FLAG
3
05813-024
Figure 23. Interfacing to a Blackfin DSP
Figure 24. Interfacing to an ADSP-21065L DSP