Sierra Wireless MP 875 Digital output devices, Analog input devices

MP875 Modem User Guide
60 2130808
Digital output devices
Digitaloutputdevicesarethosethathaveonlytwostatesand
thestateiscontrolledbyasignalfromtheMPmodem.Any
devicethatistobeswitchedonandofffrom3GWatche r
wouldbeinstalledasadigitaloutputdevice.
Adigitaloutputcanbeconnectedtotwoofthepinsonthe
DB15HDconnector:Pins3and11.(Thesecanbeusedfor
eitherinputoroutput.)
Note: Before using the input/output lines, you must configure them as
inputs or outputs.
Typic allyadigitaloutputdeviceshouldbeconnectedbetween
Ground(pin10)andtheoutputport(Pin3or11).
Figure 6-3: Wiring for using Pin 3 (digital output) as an electronic switch. Pin
10 is Ground.
ThedigitalI/Oportsprovideopen‐collectoroutputtoa
maximumof500mA.
Analog input devices
Analoginputdevicesarethosethatgenerateasignalof
varyingvoltage ,basedonthestateofaninstrumentorgauge.
Anexampleofananaloginputdevicemightbeasensorthat
detectsthevehicle’sspeed.
Ananaloginputcanbeconnectedtofourofthepinsonthe
DB15HDconnector:Pins7,8,14,and15.