ADLINK DAQe-2214 - Manual (Page 88)

76 Operation Theory
System Synchronization Interface
The SSI (System Synchronization Interface) provides the DAQ
timing synchronization among multiple cards. In DAQ-/DAQe-
2213/2214 card, a bi-directional SSI I/O provides a flexible con-
nection among cards and allows one SSI master to output the sig-
nal and up to three slaves to receive the SSI signal. The SSI
signals are designed for card synchronization only and not for
external devices.
In PCI form factor, there is a connector on the top right corner of
the card for the SSI. Refer to section 2.3 for the connector posi-
tion. All the SSI signals are routed to the 20-pin connector from the
FPGA. To synchronize multiple cards, you can connect a special
ribbon cable (ACL-SSI) to all the cards in a daisy-chain configura-
tion.
The four (DAQ-/DAQe-2213) or six (DAQ-/DAQe-2214) internal
timing signals could be routed to the SSI or the PXI trigger bus
through software drivers. Refer to section 4.6 for detailed informa-
SSI Timing Signal Setting Function
SSI_TIMEBASE
Master Send the TIMEBASE out
Slave
Accept the SSI_TIMEBASE to replace the internal
TIMEBASE signal.
SSI_ADCONV
Master Send the ADCONV out
Slave
Accept the SSI_ADCONV to replace the internal
ADCONV signal.
SSI_SCAN_START
Master Send the SCAN_START out
Slave
Accept the SSI_SCAN_START to replace the internal
SCAN_START signal.
SSI_AD_TRIG
Master Send the internal AD_TRIG out
Slave Accept the SSI_AD_TRIG as the digital trigger signal.
SSI_DAWR
Master Send the DAWR out.
Slave
Accept the SSI_DAWR to replace the internal DAWR
signal.
SSI_DA_TRIG
Master Send the DA_TRIG out.
Slave Accept the SSI_DA_TRIG as the digital trigger signal.
Table 4-8: SSI Timing Signal and Functions