Service manual

7-1
March 2000
Part No. 001-3139-502
VOTER DIAGNOSTIC MODULE (VDM)
SECTION 7 VOTER DIAGNOSTIC MODULE (VDM)
7.1 DESCRIPTION
The Voter Diagnostics Module (VDM), in the
Switch, is the data communication buffer between the
SMM and the Voting System. The type of data
exchanges between the Voting System and the VDM
pertains to: Memory Read of the voters; Receiver Site
Enable/Disable; and Alarm/Control Information.
The Voter Diagnostic Module is a Basic Board
Module (BBM) with voter software installed that
communicates to the receiver voter system. The
VDM communicates to the System Management
Module via the Intra-Terminal Data Bus (IDB) and to
the Receiver Voter Module(s) (RVMs) via the Voter
Diagnostic Bus (VDB). Voice communication does
not take place on this module.
The VDM passes messages from the SMM
receiver to enable and disable sites. The VDM polls
the voter shelf for alarms and passes the information
to the SMM. See Appendix E.
The VDM communicates with the Voter System
at 1200 baud. The VDM polls the Voter System every
2-seconds for data or alarms.
Figure 7-1 VDM BLOCK DIAGRAM
Figure 7-2 DATA BUSSES