VTI Instruments EX1629 - LXI Trigger Bus; TEDS Transducer Support

VTI Instruments Corp.
60 EX1629 Basic Operation
LXI TRIGGER BUS
The EX1629 provides an LXI compatible trigger bus connector. For more information on the LXI
Trigger Bus, please visit www.lxistandard.org and refer to LXI Standard Revision 1.1 and
LXI Trigger Bus Cable and Terminator Specifications Rev 1.1.
Pin 1 Pin 13
Pin 14 Pin 25
FIGURE 3-11: TRIGGER BUS DB-25 CONNECTOR
Pin
Signal
Pin
Signal
1
+3.3 V
14
RP_TRIG_P0
2
GND
15
RP_TRIG_N0
3
RP_TRIG_P1
16
RESERVED
4
RP_TRIG_N1
17
RP_TRIG_P2
5
GND
18
RP_TRIG_N2
6
RP_TRIG_P3
19
GND
7
RP_TRIG_N3
20
RP_TRIG_P4
8
GND
21
RP_TRIG_N4
9
RP_TRIG_P5
22
GND
10
RP_TRIG_N5
23
RP_TRIG_P6
11
RESERVED
24
RP_TRIG_N6
12
RP_TRIG_P7
25
RESERVED
13
RP_TRIG_N7
TABLE 3-7: LXI TRIGGER BUS CONNECTOR PIN ASSIGNMENTS
TEDS TRANSDUCER SUPPORT
The EX1629 supports reading and writing to Transducer Electronic Data Sheets (TEDS) devices
that implement the IEEE 1451.4 standard. Each channel (0 through 47) functions as a 1-Wire bus
master, although only one channel can be active at a time, reading, or writing. Only one TEDS
device per channel is supported.
There are two software interfaces to support TEDS devices, one that is tailored specifically for the
Dallas/Maxim DS2430 part and one that is more general purpose that will work with any 1-Wire
TEDS device, implementing the MicroLAN (MLAN) protocol. The former is deprecated; the
latter, MLAN interface, is more general purpose and should be used by all new applications. The
MLAN protocol is documented in IEEE 1451.4-2004 Annex G. See the MicroLAN (MLAN)
Primer and associated sections for more information.