LabVIEW
NI visa writes when serial port closes
Solved!
@Sam_Sharp wrote:
While USB hubs are good for providing more power, they are not good for the reliability of the connection as you'd have all 7 devices essentially multiplexing through a single USB port for communications which could cause issues. The best solution would be to use a PCI or PCIe card with 8 serial ports, then either using a single usb to 8 serial port box or adding more USB ports via PCI/PCIe.
Did you try my suggestion about flushing the transmit buffer?
Hi Sam,
I am now going to use a chassis i have with a PXI 8430/16. Its pretty much exactly what youre talking about. I also did try your suggestion of flushing the transmit buffer. Typically i flush the buffers when i open the port. It didnt fix the issue though, even if i opened and closed the port for every write i performed.
@RTSLVU wrote:
@matt198717 wrote:
Hi Bill,
I actually cant find the power ratings for the hub, its a rosewill RHUB-500, some off the shelf thing I thought might work better than the native ports. I would agree it could definitely be either power issues or enumeration issues with all the adaptors and then the hub. I have an NI chassis with a PXI 8430/16. Im going to charge my devices for a few hours and then give that a try. If the problem is fixed then it is either the adaptors or the hub. I ran a test similar to this with a lot more data transfer going on and 6 USB converters and didnt see an issue for around 3 weeks.
Rosewill (Newegg house brand) is cheap junk.
Youre entirely right, but it was working better than the native ports on the desktop. By no means is it an industrial piece of equipment, i just had it lying around and thought some external power might help.Ive got the PXI chassis out now though. I assume i wont have any issues with it now.
