MSComm32 and SComm64 have the same syntax and functionality
SComm1.DTREnable = value
value = SComm1.DTREnable
A Boolean Expression indicating the current state of the DTREnable property.
SComm1.DTREnable = True
While the port is open this property can be used to set the state of the DTR line on or off. If set before the port is opened then this value takes effect as soon as the port is opened and go off again as soon as the port is closed.