18 px] [size=turn with a USB serial port line test no problem, but received up to collect a few sensor data is not received, the sensor for marposs will always hair G25 measured data, then jumped into the following two events comEvDSR 4 data - set ready line change,
ComEvCD 5 carrier detect linear change, explain

 Option Explicit 

Private Sub Command1_Click () 
'... To send data 
MSComm1. OutBufferCount=0 '... Empty the output register 
MSComm1. The Output=Text1. Text '... To send data 

'MSComm1. The Output="H" 
End Sub 

Private Sub Command2_Click () 
'... Out 
With MSComm1 
If the PortOpen=True Then 
. PortOpen=False 
End the If 
End With 
Unload Me 
End Sub 
Private Sub Form_Load () 
'... Initialize the 
MSComm1.Com mPort=2 '... Use Com1 port 
MSComm1. Settings="9600, n, 8, 1" '... Set the communication parameters 

'MSComm1. An InputMode=comInputModeText text retrieve data 

MSComm1. InputLen=0 'sets or returns a read number of bytes, from the receive buffer 0 indicates a read all data 
'MSComm1. InBufferCount=0 
'MSComm1. OutBufferCount=0'... Empty the output register 
MSComm1. OutBufferSize=512 


MSComm1. InBufferSize=5120 



MSComm1. RThreshold=1 
MSComm1. SThreshold=1 

MSComm1. PortOpen=True '... Open the serial port 




End Sub 

Private Sub Mscomm1_Oncomm () 
'... Communication event 
'Dim s As String 
Select Case mEvent MSComm1.Com 

'the EVENT CASES in 
Case comEvReceive 

'Case s=MSComm1. Input 
Text2. Text=Text2. Text + MSComm1. Input + "" '... Accept display data 
'MSComm1. InBufferCount=0'... Empty the input register 
'Case Else 

Case comEvCD 
MsgBox "5 carrier detect linear change," vbCritical, "communication events: 
"Case comEvCTS 
MsgBox "3 clear - to - change the send line", vbCritical, "communication events: 
"Case comEvDSR 
MsgBox "4 data - set ready line change," vbCritical, "communication events: 
"Case comEvRing 
MsgBox "6 ringing detection," vbCritical, "communication events: 
"Case comEvSend 
MSComm1. OutBufferCount=0 
'MsgBox "1 send events", vbCritical, "communication events: 
"Case comEvEOF 
MsgBox "7 end of file", vbCritical, "communication events," 


'the Error cases in 
Case comEventBreak 
MsgBox "1001 receives the interrupt signal," vbCritical, "communication error: 
"Case comEventCTSTO 
MsgBox "1002 Clear - to - send timeout", vbCritical, "communication error: 
"Case comEventDSRTO 
MsgBox "1003 Data - set ready" overtime, vbCritical, "communication error: 
"Case comEventFrame 
VbCritical MsgBox "1004 frame error", "communication error: 
"Case comEventOverrun 
MsgBox "port 1006 speeding," vbCritical, "communication error: 
"Case comEventCDTO 
MsgBox "1007 Carrier detect timeout," vbCritical, "communication error: 
"Case comEventRxOver 
MsgBox "1008 receive buffer overflow" vbCritical, "communication error: 
"Case comEventRxParity 
VbCritical MsgBox "1009 Parity error", "communication error: 
"Case comEventTxFull 
MsgBox "1010 transmission buffer is full," vbCritical, "communication error: 
"Case comEventDCB 
MsgBox "1011 retrieval port equipment control block (DCB) when accidental error", vbCritical, "communication error: 
"End the Select 
End Sub 

CodePudding user response:

CodePudding user response:

Just learning VB to write a serial port good sad, thank you for your guidance

CodePudding user response:

Is this sensor communication requirements, saying how close the flow control?

CodePudding user response:

Come and learn, LZ refueling

CodePudding user response:

Don't pop-up dialog debugging,

CodePudding user response:

Don't pop up, although program can run, but only receive a few data behind, there is no response

CodePudding user response:

Don't pop up, although program can run, but only receive a few data behind, there is no response

CodePudding user response:

In exchange for better U turn seton try, based on the FT232 chips, for example,

Or in a machine with a serial port debug through, with a U turn string test,

CodePudding user response:

As no clear input buffer, know not have any effect
According to my experience

Receive events in general form is

 Dim sdata As String 
MSComm1. InputLen=0 
If MSComm1.Com mEvent=comEvReceive Then 
MSComm1. InputLen=0 
Sdata=https://bbs.csdn.net/topics/MSComm1.Input 
MSComm1. InBufferCount=0 
End the If 

You can set the trigger MSComm1_OnComm conditions -- -- -- -- -- - mscomm1. RThreshold=do you want the length of the

CodePudding user response:

Both the cache is set to the same, why don't you see
MSComm1. OutBufferSize=512


MSComm1 InBufferSize=5120

CodePudding user response:

In VB serial control is not good with no tone down the value of multiple serial port debugging before a few not receive data, to give up in the earlier
Go to the next pcommlite_1. 6 very reliable to use

CodePudding user response:

The so-called bad, is often not used, wrong,

CodePudding user response:

refer to 12 floor of123 reply:

so-called bad to use, is often not used, with no,

In a nutshell, is to "pull out excrement lai toilet",

CodePudding user response:

What most people? nullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnullnull