I have written a bash script program to sequence query the status of the discrete inputs. This occurs at just under 1 second intervals. My question, is there a limit on read/query cycles with the invoked technology used? Another way to ask, can I wear this thing out? Using both 8 and 16 channel gpio USB modules. Any comment or wild guesses welcomed.
Hello Curtis, Our USB GPIO devices can accept one outstanding command at any point of time (No command FIFO inside). The maximum number of commands these devices can do is in the order of 1000 - 2000 per second. But it can be as low as a few hundred commands depending on the other factors I mentioned earlier. Thanks, Tom Numato Lab
Tom, Thanks for your answer. Perhaps I could have done a better job of asking what information I am seeking. My specific concern is how many queries (total) can this device handle (lifetime). I know this sounds odd, but running this device 24 x 7, I had one that quit working. My only though was I may have exceeded some sort of theoretical read 'cycle' limit (device lifetime) count. That specifically is my question... can I wear it out given the type of technology used in the unit? My thoughts probably stem from some bad experiences with SSD having a theoretical limit for I/O operations for computer storage then crash. I'm no expert in the technology involved, so hence the question. The script I wrote queries the device around 12 times per second (but different i/o ports) sequentially and it runs 24 x 7. I use it for home automation application. Are my concerns valid, and why would the previous unit fail to mount in Linux (/dev/ttyACM0) after 4 months of pounding it with continuous queries? Thanks
Hi Curtis, Our GPIO devices does not have any cycle limits as such other than the MTBF specified by the component manufacturers. Most components has MTBF rated for many tens of years. But those numbers based on tests in controlled environments. In a practical environment, various factors such as static electricity, EMI/RFI can damage the devices. Your test case is nowhere near to have a potential wear/longevity related problem. I'm guessing it should be something else. I think we should do a bit of research and find out what failed and why. This certainly will ehlp improve the product and make it more reliable over time. Please create a ticket at our contact us page so we can discuss further. Thanks, Tom Numato Lab
