MSComm and a Scanner
in [Visual Studio]
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From: Henning on 5 Dec 2006 18:59 "Dave" <davegp2(a)msn.com> skrev i meddelandet news:1165344249.348331.193110(a)f1g2000cwa.googlegroups.com... > Henning wrote: > > Hi Dave, > > > > Excuse me for starting to feel a little dizzy. Do we really talk about an > > ETHERNET hub? If so, how on earth can you get any data from the scanner with > > MSComm???? Are you sure that it is not an USB hub, and an USB to RS232 cable > > to your computer? Is there another connection? > > > > Hi Mr. Henning and All, > > Thank you (all) for staying current on this post. I am sorry for your > "dizzy" feeling and I will try to clear it up. I may have I used > the term "hub" too loosely. > I am a retrained manufacturing (production - inventory control) guy > who years ago lost his tractor manufacturing job due to plant closure. > Forgive my rookie status when it comes to things LAN based. > We have a part-time network administrator (private consultant & very > capable) who does the LAN stuff. He said this is not a "USB Hub" > hookup. To connect the scanner originally (two years ago) he says > it's really going through a switch not a hub over a CAT cable via a > MAC address. (HTH). > You understand the connection precisely Scanner > PowerWedge > to the > LAN. > To answer your question about how the MSComm is involved: When we > installed the scanner (for light duty) I simply dropped an MSComm > control on a form and in the "Private Sub MSComm1_OnComm()" event I > placed the following code "Text1.Text = MSComm1.Input." That line > reads the scanner. It has worked fine for 2 years; the only other code > in that event is a little string manipulation, and I send it to another > sub to store it as a record in an Access db table. > > The app reads the string every 3:05 minutes, (based on the Scan time) > plus or minus a second or two. > This time delay has not been a problem in the past, but sooner-or-later > it will be. I just assumed in the past that the MSComm control sent > out some kind of read signal to the COM port on based on an internal > timer but I was informed here, that's not how it works. The fact that > the delay is based upon the scan time, that alone should have told me > this is a scanner based delay, not an MSComm issue. > > As you suggested, should I be trying the Winsock? > > I hope this "sorts" you (and all other helpful posters) out as you > put it. > > Thanks again (everyone here) for your responses and questions... hope > you may be able to straighten up my "dizziness" here J. > > Dave > Lets forget the computer end for now. Someway you do get the code, don't ask me how;) I've used barcode-scanners in a few projects, and they were all programmable with all kinds of parameters. Lets say there is one of the units at the scanner-side that expects a cr after the code. If the scanner doesn't have a cr postamble, there might be a timeout that evetually sends the code 3 min. later. I think this is the end to start looking for the delay. As someone suggested, what happens if you connect the scanner directly to the computer. Connecting with KeyboardWedge, you can check the code sent in Notepad. There should be a male and female keybord connector. Connecting with RS232, you can use your program. Lets hope there is 9/25-pole std. RS232 connector to the ICPCON. Output from the PSC PW must be connectable to RS232 and input to your program. /Henning
From: David Youngblood on 5 Dec 2006 20:32 "Dave" <davegp2(a)msn.com> wrote in message news:1165344249.348331.193110(a)f1g2000cwa.googlegroups.com... > Henning wrote: > > Hi Dave, > > > > Excuse me for starting to feel a little dizzy. Do we really talk about an > > ETHERNET hub? If so, how on earth can you get any data from the scanner with > > MSComm???? Are you sure that it is not an USB hub, and an USB to RS232 cable > > to your computer? Is there another connection? > > > > Hi Mr. Henning and All, > > Thank you (all) for staying current on this post. I am sorry for your > "dizzy" feeling and I will try to clear it up. I may have I used > the term "hub" too loosely. > I am a retrained manufacturing (production - inventory control) guy > who years ago lost his tractor manufacturing job due to plant closure. > Forgive my rookie status when it comes to things LAN based. > We have a part-time network administrator (private consultant & very > capable) who does the LAN stuff. He said this is not a "USB Hub" > hookup. To connect the scanner originally (two years ago) he says > it's really going through a switch not a hub over a CAT cable via a > MAC address. (HTH). > You understand the connection precisely Scanner > PowerWedge > to the > LAN. > To answer your question about how the MSComm is involved: When we > installed the scanner (for light duty) I simply dropped an MSComm > control on a form and in the "Private Sub MSComm1_OnComm()" event I > placed the following code "Text1.Text = MSComm1.Input." That line > reads the scanner. It has worked fine for 2 years; the only other code > in that event is a little string manipulation, and I send it to another > sub to store it as a record in an Access db table. > > The app reads the string every 3:05 minutes, (based on the Scan time) > plus or minus a second or two. > This time delay has not been a problem in the past, but sooner-or-later > it will be. I just assumed in the past that the MSComm control sent > out some kind of read signal to the COM port on based on an internal > timer but I was informed here, that's not how it works. The fact that > the delay is based upon the scan time, that alone should have told me > this is a scanner based delay, not an MSComm issue. > > As you suggested, should I be trying the Winsock? > > I hope this "sorts" you (and all other helpful posters) out as you > put it. > > Thanks again (everyone here) for your responses and questions... hope > you may be able to straighten up my "dizziness" here J. Perhaps it actually takes 3+ minutes to complete a scan. The cheap H-P scanner I have at home has these specs, Scan Speed: 90 secs: 4 � 6 in color photo to MS Word 180 secs: OCR letter size B/W text to MS Word 150 secs: B/W line art to MS Word David
From: Dave on 6 Dec 2006 10:26 AND THE ANSWER IS: RThreshold = 1 (Not 0) Receive Threshold property of the MSComm control. (duh) Very informative posts, Thanks. Dave
From: Henning on 6 Dec 2006 12:00 "Dave" <davegp2(a)msn.com> skrev i meddelandet news:1165418786.067545.170120(a)j44g2000cwa.googlegroups.com... > AND THE ANSWER IS: > > RThreshold = 1 (Not 0) > > Receive Threshold property of the MSComm control. (duh) > > Very informative posts, Thanks. > > Dave > Great! And now if you haven't rewritten the OnComm code, I dare to bet there is another problem. The textbox just showing one character at a time ;) /Henning
From: NewsGroup on 6 Dec 2006 23:32
"Dave" <davegp2(a)msn.com> wrote in message news:1165418786.067545.170120(a)j44g2000cwa.googlegroups.com... > AND THE ANSWER IS: > > RThreshold = 1 (Not 0) > > Receive Threshold property of the MSComm control. (duh) > > Very informative posts, Thanks. > > Dave > I suggested that 4 days ago. Mike. |