Operations
29
PCIe-9529
Figure 3-10: SSI Architecture
The three internal timing signals can be routed to the SSI bus
through software drivers. Physically, signal routing is accom-
plished in the FPGA, with cards connected together through the
SSI bus achieving synchronization on the three timing signals, as
follows.
3.6.1
SSI_TIMEBASE
As output, the SSI_TIMEBASE signal transmits the onboard ADC
timebase through the SSI bus. As input, the PCIe-9529 accepts
the SSI_TIMEBASE signal as the source of the timebase.
3.6.2
SSI_SYNC_START
Before a SSI master issues SSI_AD_TRIG to other SSI slaves,
SSI_SYNC_START is first asserted by the master card, synchro-
NOTE:
NOTE:
Different signals cannot be routed onto the same trigger bus
line.
SSI_AD_TRIG
SSI_SYNC_START
SSI_TIMEBASE
SSI Interface
SSI Bus[0:7]
Timing Control
SSI Bus[0]
SSI Bus[5]
SSI Bus[1]
SSI_AD_TRIG
SSI_SYNC_START
