Chapter4 HardwareOverview
NI5102 User Manual 4-22 ni.com
Master/Slave Operation
You can usetwo or more NI 5102 digitizers in one system to increase the
numberof channels for your application by synchronizing devicesover the
RTSI bus or PFI lines.
Usethe RTSI bus for synchronizing two or more NI 5102 (PCI, PXI, ISA)
devices.For the NI 5102 (PCMCIA, USB), you must use the PFI lines.

Restrictions

Toensure proper master/slave operation of your NI 5102, you must observe
the following restrictions:
•Youmust use all channels for acquisition. For example, if you want to
usethree channels at a time, you cannot use two channels on the master
and one channel on the slave,you must use four channels for data
acquisitionand discard data on the fourth channel.
•Thedesired pretrigger number of scans and total number of scans must
be a multiple of four.This is a hard ware limitation.
•Thereis a maximum of one sample clock tim ing jitter between master
and slavedevices.

Connecting Devices

♦NI5 102 (PCI, PXI, ISA)
Youcan synchronize NI 5102 (PCI, PXI, ISA) devices over the RTSI bus.
Youcan configure a system where a NI 5102 (PCI or ISA) can be the
master devicecontrolling a mix of NI 5102 (PCI, ISA) slave devices. The
NI5 102 (PXI) can control only other NI 5102 (PXI) devices. The NI 5102
(PXI)has the RTSIconnectivity on the bus connector; the optional
RTSIbus cable is not needed. However, you need a RTSIbus cable to
synchronizetwo or more NI 5102 (PCI or ISA) digitizers over the RTSI bus
asfollows:
1. Ifyou are using multiple NI 5102(PXI) digitizers, skip this step. If you
areusing the NI 5102(PCI or ISA), connect the master device with the
slavedevice over the RTSI connector. The cable and connector are
keyedso there is only one way to insert the cable in the con nector.
2. Ensureth at no other devicein the system is configured to output its
internaltimebase on the RTSI bus clock line. The safest approach is
to restart your system, if possible.