Serial port test ( serial )

Thread Starter

allied

Joined Mar 11, 2007
33
Is there any way check or know the serial port information & do SERIAL OUTPUT TEST of my computer to make sure theres no problem without buying a software to test it like GRAHAM utilities OS/2 version...

ADVANCED THANKS

Allied
 

Papabravo

Joined Feb 24, 2006
21,094
Yes there is.
Write a small program, or send a file, that sends the same character continuously. With an oscilliscope on transmit data you trigger on the start bit, get the whole character on the screen of the oscilliscope and identify the start bit, the stop bit, the data bits and any parity bits. Now change the character and repeat the process. This will tell you if the transmit bit timing is correct.

Now take a short piece of wire and loop the transmit data back to the receive data. If you can receive what you send you will be in good shape.
 

Papabravo

Joined Feb 24, 2006
21,094
If you want to go much further in this field I would suggest that you become intimately familiar with the osciloscope. If you insist on trying to work with one arm tied behind your back you will be severly limited in what you can accomplish.
 

Thread Starter

allied

Joined Mar 11, 2007
33
This is regarding with my first post about serial port. The reason I ask about that is bec. My boss will assign me to service and to solve the problem that they trying to solve. They finally give up even I told them all the things I done before they left and also we talk thru phone to able guide them. I told them step by step procedure how I do it before they left and even on the phone when they arrive on the hospital to make sure that we do it correctly...... that the reason I ask about the serial port connections bec. we all 100% meet all the requirements and follow all the instructions....I think the culprit one is the serial port...This the story...

Our company sell hematology analyzer unit it is used for complete blood count used in hospital . Our unit has feature that you can simultaneously transfer the result with other computer the problem is that my boss experienced problem doing that . We have operators manual for the software to able install the software to the computer. Im 100% we all meet the requirements that software required( Computers specification..OS, memory required, display setting...etc...) the computer were using is brand new we buy this to make sure we meet all requirements.. & also that Im 100% that they follow correctly the procedure how to download it bec. im talking them in the phone when they do it to make sure they do it correctly... Im had hands on experienced doing that before so its very easy for me to make sure that they do it correctly...SO I JUST TOLD THEM WHAT I ACTUALLY DO BEFORE.... The operators manual require that RS 232 should be connected in the COMP 2 of the hematology unit then connect it on the RS 232 port of the computer. You may told me that may be they not properly connected the connection of cable...That is not because the computer cannot able lunch the application of the software if there no hematology unit connected in the computer. This what happen when they test the unit to count a sample blood the computer will display the result after the unit finish counting the blood the hematolgoy unit pop up a COMMUNICATION ERROR (I actually never experienced that problem bec after doing all that I succesfully transfer a result). Im lucky to find the device manager in my computer in the office. I told them what is the COMP port in their computer they told it selected on the COM 1 I just told them to activate the COMP 2 to able to transmit hoping it will becacuse my computer with the hematogy unit was in the COM 2 after viewing it on the device manager . After they change it and test the unit again test to count a blood after the hematology unit finished counting the blood the COM ERROR gone but still theres no tramission of the data on the computer. Presently I searched google about communications port problem I not lucky to find same problem some problem i found is they concern on the modem. But Found I found An article SELECTING THE PROPER PORT stating the (Com 1 and com 2) and (com 2 and com 4) that complicates the situation...http://www.palmtoppaper.com/ptphtml/15/pt150093.htm
Is this possible?

I just want to equipt my self the knowledge to able troubleshoot when I go in that place bec. The hospital is very far and I wil ride a plane to get there I very very important is want my visit to be succesfull. I really desperate need your help guys....

( I noticed that my letter to long...hope you understand .....Thanks)

Allied
 

Papabravo

Joined Feb 24, 2006
21,094
Have your company purchase a FLuke Portable LCD oscilliscope. It will be much cheaper then the plane tickets that he appears willing to buy. If worse comes to worse you can hire me to fix the problem at the factory where it should have been fixed in the first place.
 

SgtWookie

Joined Jul 17, 2007
22,230
Check the computer's BIOS settings. It may be that your computer might be trying to share IRQ's between com ports or other devices - this doesn't work very well resulting in conflicts.

If your BIOS supports legacy ISA devices, set your COM1 to IRQ 4, address 3F8h and your COM2 to IRQ 3, address 2F8. If the computer has more com ports, disable them.

Then, boot up Windows, and uninstall the com ports from your Device Manager. Re-boot to let Windows re-detect them.

Then retry your application.
 

nomurphy

Joined Aug 8, 2005
567
You should be able to check under Device Manager to see if the port is enabled and Windows thinks it's okay.

Then, there is an accessory application in Windows called HyperTerminal. If you use a small piece of wire (or a low value resistor < 100 ohms) to connect the Tx to Rx on the Comm port (loopback), you can use HT to check actual operation of the port by typing on the keyboard and receiving the same.
 
Top