ADLINK PCIe-7350 - Manual (Page 56)

46 Function Block and Operation Theory
3.7.6 DI DMA in Burst Handshaking Mode
The burst handshaking mode is a fast and reliable data transfer
protocol. It has both advantage of handshaking mode and continu-
ous mode.
In DI burst handshaking mode, DI-REQ signal will be active by
external device when it is ready to send DI data and sample clock.
And then DI-ACK signal will be generated by PCIe-7350 when it is
ready to receive DI data from external device.
External device should start to send DI data after it detect DI-ACK
signal is active. DI data transfer between PCIe-7350 and external
device should be continued when both DI-REQ and DI-ACK are
active. When DI FIFO of PCIe-7350 becomes almost full, DI-ACK
signal will be inactive. External device should stop to send DI data
and sample clock after it detects DI-ACK signal inactive. The oper-
ation sequences are listed as follows:
Step1: Configuration

Define DI port configuration (32/24/16/8-bits data width)

Define DI logic level configuration (3.3/2.5/1.8 V)

Define DI sample clock configuration (only external)

The phase shift function is available when external clock
is a free-running clock (not a strobe signal) and external
clock rate is from 2 MHz – 50 MHz.
 Define DI-REQ and DI-ACK signal (AFI0 ~ AFI7)
 For example: if configure AFI3 as DI-REQ and AFI4 as
DI-ACK, and then you must connect the handshaking
signal (DI-REQ and DI-ACK) of external device to the
AFI3 and AFI4.
 Define DI starting mode configuration (NoWait or WaitTRIG)
 If choose WaitTRIG, you can define start trigger source
to be software trigger or external trigger (DI-Start or DI-
TRIG) from AFI0 ~ AFI7.

Define DI data count