User Guide

Global Positioning System (GPS)
Rev 3.0B Feb.08 91
Figure 10-9: AceManager : PinPoint - #IG
Store and Forward
StoreandForwardcanprovideseamlesscoverageevenin
areaswithintermittentcellularcoverage.IfthePinPointX
leavescoverageorhasverylowsignal(anRSSIof‐105or
lower),itwillstoretheGPSmessagesinmemory.Whenthe
modemre‐enterscellularcoverage,itwillthenforwardthe

messagesasconfigured.ThePinPointXcanalsostore
messagesandsendthemtotheserverinapacketratherthan
individuallytoconservebandwidth.
EnableStoreandForwardusing*PPSNF.Youcanalso
determinehowyouwantthemessagessentusing*PPSNFB
and*PPSNFM.
Figure 10-10: AceManager : PinPoint - *PPSNF, *PPSNFB, *PPSNFM
• Normal‐Eachreportissentimmediately.
• Polled‐Reportshelduntilrequestedbytheserver.
• Grouped‐Reportshelduntilthetotalisequalorgreater
than*PPSNFMwhichsetsthepacketsizeofgrouped
reports.
Store and Forward Reliable Mode
TheStoreandForwardReliableModeallowsthePinPointXto
ensureallmessagesarereceivedbytheserverevenifthe
connectionbetweenthemgoesdownforaperiodoftime(such
whenavehiclepassesthroughalocationwherethecellular
signalisweakornon‐existent).
WithReliableMode,*PPSNFR,enabled,thePinPointXwill
transmitasequencenumber(1to127)aspartofapacketof
messages(maycontainoneormorereports).Toreduce
overhead,theserveronlyacknowledgesreceiptofevery
eighthpacket.ThePinPointXconsidersthat8a“window”of
outstandingpackets.