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SNAPlink User Guide — 116-081614-031-A000
Data
UART
SNAPlink adapters contain two UART (Universal Asynchronous Receiver/Transmitter)
connections, one for the USB port and one for the serial communications (RS-232 or RS-
485/422) port. This setting indicates which port is connected to your serial device and
where the serial data should be transmitted or received. The factory default is to send all
serial data through either the RS-232 DE9 or RS-485/422 terminal block and NOT through
the USB cable. This leaves the USB port as the means to communicate with EasySet.
You can change this arrangement, but it will make your device unreachable via the USB
port for further programming by EasySet. If you choose "USB" using this Data UART
setting in EasySet and later need to reprogram the device, the easiest method is to reset
the device to its default settings. Alternately, if your computer has an RS232 port or if you
have an adapter to connect to the RS-232 or RS-485 port on your SNAPlink device, you
could use that connection to connect to EasySet.
Bps
Rate
Set the SNAPlink bps rate to match that of your serial device. The bps rate for all devices
can range from 300 to 115,200. Adapters can send chunks of data in bursts up to 115,200,
and safely sustain a maximum of 19,200 bps if one device is sending data, or 9,600 if two
devices are constantly sending data to each other.
SNAPlink devices default to 9,600 bps. If EasySet isn't available, you can modify your bps
rate using DIP switches inside the SNAPlink enclosure. See the
DIP Switch 1
section for
details. Defaulting the device by holding the button during power-up will set it to the value
specified by the DIP switches and clear other routing configuration changes to defaults.
Changing the DIP switches and power cycling the device will change the bps rate (and/or
SNAP radio channel) without affecting other configuration changes.
Data
Bits
Set the number of data bits to 7 or 8. The default is 8.
Parity
Set the parity to none, odd, or even. The default is none.
Stop
Bits
Set the stop bits to 1 or 2
1
. The default is 1.
Flow
Control
This setting should only be enabled for devices needing flow control. RS-485 and RS-422
devices always have flow control enabled. For RS-232 devices, the default is disabled.
If you do not have EasySet available, you can modify your flow control setting using a
DIP switch inside the SNAPlink enclosure. See the
DIP Switch 1
section for details.
Defaulting the device by holding the button during power-up will set it to the value
specified by the DIP switch.
1
Early SNAPlink devices required that stop bits always be set to 1. The current version allows either 1 or 2.
