ADLINK PCIe-7350 - Manual (Page 58)

48 Function Block and Operation Theory
The timing diagram of DI DMA in burst handshaking mode is
shown as below:
Figure 3-19: DI Burst Handshaking Timing Diagram
3.7.7 DO DMA in Burst Handshaking Mode
In DO burst handshaking mode, DO-REQ signal will be active by
PCIe-7350 when it is ready to send out DO data. And then DO-
ACK signal should be generated by external device when it is
ready to receive DO data. Once DO-ACK is active, external device
has to keep DO-ACK active until its input buffer is almost full. The
operation sequences are listed as follows:
DO DI Data
DI Sampled Clock
(from external)
DI -REQ
(Active High)
DI -ACK
(Active High)
D1 D2 D3 D9 D7 D8
PCIe-7350 is ready to
receive DI data
External Device is ready to send DI data
DI data transfer starts
D5
PCIe-7350 is not ready
to receive DI data
Wait DI-REQ
asserted
Wait DI-ACK
asserted
DI data transfer stops DI data transfer re-start
(DI FIFO is full)
(DI-REQ & DI-ACK
are all asserted)
(DI-ACK is de-asserted) (DI-REQ & DI-ACK
are all asserted)