Four Channel, Serial (RS232/422/485) (Module P8) /Isolated RS-422/RS-485 (Module PC)68C3 Operations Manual North Atlantic Industries, Inc. 12/19/2014Rev: 2014-12-19-0947 www.naii.com Page 89 of 330Serial Communications SpecificationsSpecifications RS232 (P8 only) RS422 RS485Mode of Operation Single Ended* Differential DifferentialTotal number of Drivers & Receivers on one line 1 driver, 1 receiver 1 driver, 1 receiver 1 driver, 32 receiversMaximum Data Rate 120 kb/s 1Mb/s Asynch4Mb/s Synch1Mb/s Asynch4Mb/s SynchDriver Output Signal Level (Min Loaded) ±5V @3kΩ load ±2.0V@100Ω load ±1.5V@54Ω loadDriver Load Impedance (Ohms) 3k min 100 54Max Driver Current in High Z State (Power On) N/A N/A ±100uAMax Driver Current in High Z State (Power Off) ±6mA@±2V ±100uA ±100uAReceiver Input Voltage Range ±15V -10V to +10V -7V to +12VReceiver Input Sensitivity ±3V ±200mV ±200mVReceiver Input Resistance (Ohms) 3k to 7k 120 10kNote: The EIA232 standard uses negative, bipolar logic in which a negative voltage signal represents logic ‘1’, and positivevoltage represents logic ‘0’. RS232 active signals are provided on the (-) pin (see pinouts) (applies to P8 only).CH1ProgrammableTransceiver(RS232/422/485)TX/RX +/- 32 KB TX32 KB RXData BuffersControlRegistersUser InterfaceTX/RX +/-32 KB TX32 KB RXData BuffersControlRegisters32 KB TX32 KB RXData BuffersControlRegistersFPGA / DSP32 KB TX32 KB RXData BuffersControlRegistersCLK +/-TX/RX +/-TX/RX +/-CLK +/-TX/RX +/-TX/RX +/-CLK +/-TX/RX +/-TX/RX +/-CLK +/-Ch2ProgrammableTransceiver(RS232/422/485)CH3ProgrammableTransceiver(RS232/422/485)Ch4ProgrammableTransceiver(RS232/422/485)Module Bus(P8) module block diagramCH1IsolatedTransceiver(RS422/485)TX(+) 32 KB TX32 KB RXData BuffersControlRegistersUser InterfaceRX(+)32 KB TX32 KB RXData BuffersControlRegisters32 KB TX32 KB RXData BuffersControlRegistersFPGA / DSP32 KB TX32 KB RXData BuffersControlRegistersCLK (+)Ch2IsolatedTransceiver(RS422/485)CH3IsolatedTransceiver(RS422/485)Ch4IsolatedTransceiver(RS422/485)Module BusTX(-)RX(-)CLK (-)TX(+)RX(+)CLK (+)TX(-)RX(-)CLK (-)TX(+)RX(+)CLK (+)TX(-)RX(-)CLK (-)TX(+)RX(+)CLK (+)TX(-)RX(-)CLK (-)(PC) module block diagram
