03-20-2013 03:54 PM
Try connecting pin 2 to 3 on your USB-serial adapter. Then, using whatever comm program ( I've come in late, do you see the USB-serial adapter in MAX?), send characters. If the adapter is working correctly, and configured correctly with your comm program, you should see the characters you are sending echo'd back, or "looped back".
03-20-2013 04:01 PM
Google Null Modem cable. You'll get a dozen explainations at least. Basically it is just two of the wires switched at the pins from transmit(TxD) and recieve (RxD) pins. How the device is wired determines which cable. I believe standard is RxD on pin 2 and TxD on pin 3. So if both devices are standard pinouts, you whould need a null modem cable. ei, When your scale talks from pin 3, it is received on pin 2 by the computer. Straight through means the device manufacturer already switched the wiring inside the device for you.
I'm no expert, but it looks to me like may need a null modem cable (now that I look at your pic again). I'm not sure what the Summit Series is vs. the Standard, (a model of your scale??). Maybe some of the seasoned veterans out there can weigh in concur or reject my input here?
03-20-2013 04:18 PM
Hi, AMP12:
Actually, all the poster has to do when using hyperterminal is to press his "print" button the equipment. This pormpts the equipment to generate an output to the serial port. Later, the poster will create code to send the print command programmatically, but the command structure is very confusing (definitely not SCPI), so we'll have to use the print button for now.
The poster provided the manual earlier in the thread if you wanted to check it out. (The manual is very confusing.)
03-20-2013 04:25 PM
Hi AMP12,
For differentiating null modem cable and straught through RS232 I used this source:
http://digital.ni.com/public.nsf/allkb/1EE0DD8AF67922FA86256F720071DECF
The scale model is Denver instruments SI-2002. The manuals are attached below.
Regards,
avi0111
03-20-2013 04:28 PM
Hi Billko,
I will not be switching my PC for now, Lab admin has not authorized me to remove the older version of LabView (8.2 and defunct for some reason). So switching back what I was using. Is there a different cable I might have to purchase to get this to work.
PS: will connect Pins 2 to pin 3 tomorrow and try commands over Hyperterminal tomorrow.
Thanks for all the suggestions,
avi0111
03-20-2013 10:19 PM
Yes. As AMP said, you will need a null modem cable according to the pinout diagram you posted.
(Didn't the manual tell you what kind of cable to use?)
03-20-2013 10:27 PM
03-21-2013 10:25 AM
@RavensFan wrote:
Yes. As AMP said, you will need a null modem cable according to the pinout diagram you posted.
(Didn't the manual tell you what kind of cable to use?)
Actually, RavensFan - the manual does NOT tell you what kind of cables to use! TThe documentation is really sub-par. 😞
03-21-2013 11:46 AM
Hi everyone,
I was going to purchase a null modem cable, and would like someone to confirm if the pins match. Basically the technical details provided on amazon is confusing. Here's the details;
And the pin requirements according to the manual is also attached. DB9 to DB9 according to the manual says pin 4 is hooked upto pin 4. So what does 1+6-4 and 4-1+6 mean on the cable I picked out.
Thanks, avi0111
03-21-2013 12:52 PM
@billko wrote:
@RavensFan wrote:
Yes. As AMP said, you will need a null modem cable according to the pinout diagram you posted.
(Didn't the manual tell you what kind of cable to use?)
Actually, RavensFan - the manual does NOT tell you what kind of cables to use! TThe documentation is really sub-par. 😞
That is a bad manual. The phrase "handwire handshake" is pretty bad also. Is that a bad translation from Chinese?
The manual doesn't necessarily say that pin 4 is connected to pin 4. It kind of gives that impression, but that makes no sense. Get the null modem cable and try that. Normally the handshaking lines are crossed just like the details you got from Amazon for a null modem cable. A straight cable, a null modem cable, male and female gender benders, should all be part of your arsenal for working with serial ports anyway. A loopback plug, a null modem adapter, and a box with LED;s that show which lines are functioning during the communcation are all useful tools also.