Key/Value pairs that can contain data to be sent to the gateway or used to validate a response from the
gateway. By default no parameters are used unless created in the relevant class files. You can add more parameters if you want to
pass additional info to the gateway.
Note that the values must be entered on the right, the left values are the parameter names and MUST not be changed.
Depending on the getway, parameter names are sent as either $_POST or $_GET values.
To add / remove parameter lines, use the +/- buttons.
Note that nothing is actually updated until the "Update Gateway" is clicked. More info on parameters on the
add gateway example page.
Note that if you prefer the values to be hidden, enable the "Always Hide Gateway Parameter Values" in your settings via the Payment tab.