User`s guide

Chapter 12 185
Sample Application Programs
Controlling Using Telnet Server
12. Sample Application
Programs
The part 3 is dedicated to setting the trigger mode.
The part 4 set the measurement parameters and data format for trace 1 in channel 1.
Clicking the button labeled as ‘Set” executes setting operation as specified with the setting
table, while clicking the button labeled as “Query” retrieves the current settings of the
E5061A/E5062A.
In the part 5, clicking the button labeled as “Auto Scale” executes auto scaling for trace 1
in channel 1.
Clicking the button labeled as “Read Trace” in the part 6 retrieves the formatted data of
trace 1 in channel 1 and displays it in tabular and graphical formats.
Clicking the button labeled as “Preset” executes the presetting operation.
Description of operation in VBA macro
Here described is operation of the VBA macro, focusing on the part related to controlling
with WinSock API.
In order to use
WinSock API, you must declare functions and define variables with a
definition file of
WinSock API, as shown in Example 12-7.
Example 12-7 Definition file of WinSock API
'This is the Winsock API definition file for Visual Basic
'Setup the variable type 'hostent' for the WSAStartup command
Type Hostent
h_name As Long
h_aliases As Long
h_addrtype As String * 2
h_length As String * 2
h_addr_list As Long
End Type
Public Const SZHOSTENT = 16
'Set the Internet address type to a long integer (32-bit)
Type in_addr
s_addr As Long
End Type
'A note to those familiar with the C header file for Winsock
'Visual Basic does not permit a user-defined variable type
'to be used as a return structure. In the case of the
'variable definition below, sin_addr must
'be declared as a long integer rather than the user-defined
'variable type of in_addr.
Type sockaddr_in
sin_family As Integer
sin_port As Integer
sin_addr As Long
sin_zero As String * 8
End Type
Public Const WSADESCRIPTION_LEN = 256
Public Const WSASYS_STATUS_LEN = 128
Public Const WSA_DescriptionSize = WSADESCRIPTION_LEN + 1
Public Const WSA_SysStatusSize = WSASYS_STATUS_LEN + 1