USB to Serial

[outwestwa]

Hi All This is another USB question that I can’t find the answer to. I’ve being controlling my lx200 classic from my desk top computer using the serial port (DB9) to the RS232 port on the telescope and it works fine. I now need to go from a USB port to the RS232 port I have a USB to serial adapter to do the conversion from USB to the RS232 port. I have what looks like no comminution to the rs232 port on the telescope. When the USB to serial adapter is plugged in to the computer it is recognised straight away and also shows up in the device manager’s property’s page under com ports as Prolific USB to Serial com port (com4). I have also changed the com. Port assignment in the control software to match. No luck there. Do I need to make up a new cross over cable or change the wiring around from the serial end of the adapter to RS232 port on the telescope? Any help would be greatly appreciated to help me resolve this problem so I can continue to set up my wireless control system. Thanks in advance for the help

[33South (Chris)]

I have come across problems with the Prolific USB/serial device before. In that it just does not seem to work on laptops without existing db9 ports.

The ATEN USB/Serial device definitely works, I got mine from ARC computers.

[programmer]

Originally Posted by 33South

I have come across problems with the Prolific USB/serial device before. In that it just does not seem to work on laptops without existing db9 ports.

The ATEN USB/Serial device definitely works, I got mine from ARC computers.

I have that cable (or at least, that's what Windows thinks it is) and it works. I don't use it for the same purpose though. Mine is for digital setting circles. I'd imagine it should work for you too. Which Windows are you using and have you installed drivers?

[outwestwa]

Hi, my laptop is a Toshiba P4, 3 GHz, 1.5 G ram and running XP pro with all up dates with driver loaded for the USB Serial adapter. As soon as the adapter was plugged in the computer found it and wanted to load the drivers.

[Exfso (Peter)]

I have a Toshiba P4 3ghz as well, and have found the USB to serial are dodgy at best. I decided on a PCMCIA card for a dedicated serial port, although expensive, they work every time..Incidentally I tried 3 different types of Serial/USB cables, and none were successful. I had one work a couple of times, then it decided that is was not part of the computer and no way was it recognised. Too much hassle in my opinion, at least on my Tosh lappy

[Astroman (Andrew Wall)]

I have come across problems with the Prolific USB/serial device before. In that it just does not seem to work on laptops without existing db9 ports.

This statement is not correct for all machines or devices. I use a Prolific Serial/USB adapter for EQMOD on my Toshiba, and it has NO Serial ports, it's the only one that works properly. I tried using a belkin one for some time and it always hung at the start of the application. USB/Serial adapters are very hit and miss, you just have to test them before getting one that works. I tried atleast 5 different brands before settling on the Prolific one.

[bird (Anthony Wesley)]

I use 4 usb-to-serial adapters on my scope to connect all the various serial bits into a single 4-port usb hub and then a single usb cable back to the laptop. Works great but you have to use one of the "real" usb-to-serial adapters, ie one that passes through all the control signals correctly and not just the data.

I've tried "dolphin" brand (my favourite cause of the thin cables) from tandy, although they don't seem to stock them anymore... they work great.

Also the ATEN adapters work ok (in fact they have the same controller as the dolphin brand) but I don't like them as much cause the cables are heavier and shorter.

cheers, Bird

[[1ponders] (Paul)]

I have a number of USB to Serial adapters and don't seem to have a problem with any of them. My favourite though is my Keyspan USB - 4 serial port adapter. Unlike a USB hub it needs no external power and works a treat on USB1 or 2.

[outwestwa]

Ok it seams most people agree that the ATEN USB to Serial adapter is worth a try so I’ve ordered one to day should take a week to get to me. I need to go all USB for my wireless control system to work no more siting out side at night and only 1 power lead is required to be run out. Thanks for all your help

[outwestwa]

Hi all. Thanks to every one for your input. The Aten USB to serial adapter arrived yesterday after installing the software and plugging every thing in I still had no communication with the telescope. The computer said the com port was open but I was not getting any data transfer. What I found was that I had to reverse the two data wires in the RJ45 to serial adapter and it worked. I now have a total wireless system for my telescope, camera, webcam with only one power cable and no second computer out side.