Beginner needs help to solve communication error problem with USB adapter and B
TMG
Posts: 6
My homework board works just fine with the RS232 cable and my desktop computer.· But, I needed the freedom of using my laptop, so I bought a USB adapter from Parallax, (http://www.parallax.com/Store/Microcontrollers/BASICStampModules/tabid/134/ProductID/93/List/1/Default.aspx?SortField=ProductName,ProductName)· for $14.99.·
This adapter uses a smaller port then what I understand to be a USB port.· I understand the USB port to be that port on the side of my laptop which is about 1/2" wide.· This adapter uses a much smaller port, about 1/4".· As a result, the required cable would have a USB sized plug on one end, and this smaller plug on the other end.· My PDA uses the same cable for backup purposes with my laptop, so I grabbed that cable to make the connections.
When I plug it all together, I see a red light flash a few times on the adapter, then a green light comes on and stays on.· When I run "Identify", it shows the basic stamp, on Com 5, and the other information is exactly the same as on my desktop.
I happen to be using a Memsic 2125 accelerometer, which I bought from Parallax, and which worked just fine last week on my desktop.· I didn't unwire the board, so I feel it remains as directed on the tutorial download.
When I run the program, the "download progress" popup comes up and I can see a green light for a brief time.· Then an error message comes up "Hardware Communication Error! Check serial cable and power supply".· I've rebotted and replugged several times, to no avail.·
The battery is almost brand new, so I don't think it is the battery.
I'm pretty sure it's the cable somehow.· But I don't know how to select another cable.· As described, they all look the same to me.· Again, I'm using the cable that came with my PDA.
Any ideas?
Thank you in advance.
Terry
This adapter uses a smaller port then what I understand to be a USB port.· I understand the USB port to be that port on the side of my laptop which is about 1/2" wide.· This adapter uses a much smaller port, about 1/4".· As a result, the required cable would have a USB sized plug on one end, and this smaller plug on the other end.· My PDA uses the same cable for backup purposes with my laptop, so I grabbed that cable to make the connections.
When I plug it all together, I see a red light flash a few times on the adapter, then a green light comes on and stays on.· When I run "Identify", it shows the basic stamp, on Com 5, and the other information is exactly the same as on my desktop.
I happen to be using a Memsic 2125 accelerometer, which I bought from Parallax, and which worked just fine last week on my desktop.· I didn't unwire the board, so I feel it remains as directed on the tutorial download.
When I run the program, the "download progress" popup comes up and I can see a green light for a brief time.· Then an error message comes up "Hardware Communication Error! Check serial cable and power supply".· I've rebotted and replugged several times, to no avail.·
The battery is almost brand new, so I don't think it is the battery.
I'm pretty sure it's the cable somehow.· But I don't know how to select another cable.· As described, they all look the same to me.· Again, I'm using the cable that came with my PDA.
Any ideas?
Thank you in advance.
Terry
Comments
www.parallax.com/Default.aspx?tabid=530
Notice that if you've already tried attaching the hardware, you may run into some troubles getting it to work properly now. Generally the driver must be installed first. Also notice the "troubleshooting" link at the bottom of that page. It may help you.
Re. the size of the connector, here's some information:
en.wikipedia.org/wiki/Universal_Serial_Bus
USB connectors on the device end use a variety of different sized connectors. What you've got is a standard "Mini-B", and if there's something wrong (/incompatible) about the one you're trying, this one will work:
www.parallax.com/Store/Accessories/CablesConverters/tabid/166/CategoryID/40/List/0/Level/a/ProductID/33/Default.aspx?SortField=ProductName,ProductName
I've found that almost any USB A to USB Mini-B cable works fine with that adapter, but I DO have one that does not, so I think that it's quite possible that your diagnosis is right - that your cable is the problem. But the driver thing is the first thing I'd look at.
Post Edited (sylvie369) : 3/8/2009 1:08:24 PM GMT