Microgate SyncLink USB - SyncLink USB Signal Specifications; Single Ended Signals (RS-232;V.28); Differential Signals (RS-422;RS-485;V.11); SyncLink USB Clock Polarity

Green LED On
Monitor the red LED (transmit) and yellow LED (receive) for indications of data transfer. These are only
valid when the green LED is on. If you see no data, verify cabling, serial interface selection (RS232, V.35,
RS530, etc), serial protocol settings and remote device status.
Signal Specifications
Each serial signal (control, status, data, or clock) is compatible with an electrical specification that is
selected through software settings. This section briefly describes the specifications supported by the
card.
Single Ended Signals (RS-232/V.28)
Single ended signals supported by the card are compatible with both RS-232 and ITU V.28 standards.
Each single ended signal uses one conductor in a cable, and all single ended signals share a common
ground conductor.
 Maximum Voltage Range: +15 to -15V (between signal and ground)
 +3V to +15V (+5V typical) = control/status signal on or data value of 0
 -3V to -15V (-5V typical) = control/status signal off or data value of 1
 Voltage between -3V to +3V = invalid (indeterminate) state
 Max cable length 50 feet
 Max data rate 20kbps
The maximum data rate of 20kbps is part of the RS-232/V.28 standards. The SyncLink card can operate
at speeds up to 120kbps depending on the cable length and loading. Longer cables and increased
loading reduces the maximum supported data rate.
Differential Signals (RS-422/RS-485/V.11)
Differential signals supported by the card are compatible with RS-422, RS-485 and ITU V.11 standards.
Each differential signal uses two conductors in a cable (signal pair). A common ground conductor is
recommended for use with differential signals to reduce common mode voltages between cable ends
which may result in incorrect or impaired operation.
 Maximum Voltage Range: +6 to -6V (between conductors in a pair)
 +200mV to +6V (+2V typical) = control/status signal on or data value of 0
 -200mV to -6V (-2V typical) = control/status signal off or data value of 1
 Voltage between -200mV to +200mV invalid (indeterminate) state
 Max cable length 4000 feet
 Max data rate 10Mbps
Longer cables and increased loading reduces the maximum supported data rate.
Clock Polarity
Synchronous serial communications (HDLC/Bisync/Monosync) may use separate clock signals to control
the timing of data signals. One clock cycle equals one bit. There are two clock edges (rising and falling)