High Voltage Amplifier
18014-D02 Rev E, Sept. 3, 2019
Page 8
www.thorlabs.com
3.2.
Computer Controlled Operation
The HVA200 may also be controlled by a command line language through the USB port
(10). This is offered to enable operation through a terminal interface or for those who may
want to write their own program to control the unit. The command language is described
below. Prior to running the command line interface, the included drivers should be
installed, the unit should be powered, and a USB cable should be connected between the
HVA200 and the host.
The terminal emulator should be set as follows:
Baud Rate: 115.2k b/s (bits per second)
Data Bits: 8
Parity: None
Stop Bits: 1
Flow Control: None
If the connection is correct and after pressing the Enter key, you will see the following:
Command error CMD_NOT_DEFINED
followed by the command prompt, “
>”
The basic structure of the interface is a keyword followed by either an equals sign (=) or a
question mark (?). The (=) or (?) will determine if the string is a command or a query. All
strings, commands and queries, must be terminated by a carriage return (CR) or pressing
the ENTER key on the computer.
The command structure is as follows:
Keyword = argument (CR)
Where “keyword” defines the function and “argument” is a numerical value followed by a
carriage return (CR).
The query structure is a follows:
Keyword? (CR)
The “keyword” defines the function and the question mark (?) indicates a query. The string
is terminated with a carriage return (CR).
There are a few exceptions to this which are noted below, also noted are unique shortcut
keys. The following table lists the commands and queries available with this device. The
prompt symbol (>) will appear on power up and after a command is accepted by the
HVA200 indicating it is ready to receive another command line.
If the keyword, format, or argument are incorrect or out of range the unit will return an
error string.
