Specifications

Section-4 Theory
November 11, 2013
4‐16
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4.4.8 SystemBus
ThesystemcontrolbusisatwentyfiveconductorribboncablewhichdistributestheCAN(ControllerAreaNetwork)
busandparallelcontrollinesfromtheMCMcardincabinetonetootherMCMcontrollersinamulticabinetsystem.
IfsystembuscommunicationswiththemasterTCU(incabinet1)areinterrupted,thecabinetbus,driveAandB
busses,andBP1throughBP4bussesalloweachcabinettooperateindependently.
ThesystembusconnectorJ6(ontherearoftheMCMcard)hasthefollowingpinassignments:
4.4.9 CabinetBus
ThecabinetbusconnectsthecabinetTCU(MCMcard)totheIPAandPAbackplanes.Thecabinetbusconnections
areshownin
Table4‐11.
Pin7ofthecabinetbuscarriesthePA_voltage_selectsignalfromtheMCMcardtotheIPAandPAbackplanes.Its
functionistosettheoutputvoltageoftheACtoDCconvertersinthePA(andIPA)modules.Pins12&25ar eforthe
CANbuswhichis
usedforadditionalexcitercommunicationsand N+1interface.
Table4‐12givesthecontrolvoltagelevelsandthecorrespondingPAandIPAmoduleACtoDCconverteroutput
voltages.
Table4‐10MCMSystemBusConnector
Pin Signal Description
1 SYS)_CAN_H CAN(5V)pass‐through
2 /CAB_AC_LOW 3.3VCMOSInput
3 /SYS_OFF_CMD 3.3VCMOSI/O
4 /SYS_RF_MUTE 3.3VCMOSI/O
5 SYS_ALC 0‐4.095VAnalogI/O
6 SYS_PS_ADJUST 0‐4.095VAnalogI/O
7 /SYS_FAULT_OFF 3.3VCMOSI/O
8 SYS_SPARE1 3.3VCMOSI/O
9 /SYS_RESTRIKE 3.3VCMOSI/O
10 SYS_SPARE2 3.3VCMOSI/O
11 SYS_CTRLR_OK 3.3VCMOSI/O
12 /SYS_FAULT 3.3VCMOSI/O
13 SYS_SPARE3 3.3VCMOSI/O
14 SYS_CAN_L CAN(5V)passthrough
15‐25 GND
Table4‐11CabinetBusPinAssignments
CabinetBusPins Function
1through6 NoConnection
7 PA_voltage_select
8through11&13 NoConnection
12 CAN(H)
14Through24 Ground
25 CAN(L)