Thursday, 7 February 2008
Kiln controller update
My first trial run discovered that relay 2 had a fault. I traced it to the pullup airwire, so after a quick solder fix, all relays work again. I also improved the connectors. In the end, I was able to sucessfully switch 240V without anything melting down.
The control board still suffers a bit from instability. Even though I grounded the large copper pour area, (which helped tremendously), it still can flake out sometimes and end up rebooting. This causes the USB connection to drop, confusing the driver.
I've been unable to figure out a combination of calling Reset() and have the C# code attempt reconnects on the USB com port to restablish a connection. I was hoping that if the C# app 'backed off' from the port, and the board reset itself, I might get it to reconnect. But so far, no dice.
I might have to decouple it from USB entirely, and instead, go to a wireless connection. That way, there is no problem with 'loosing' a usb com port. Maybe I could try a C++ app, so I really know when the app has 'let go' of the com port. In C#, there isn't any way of really knowing when it's done. And it's wrapped up in all sorts of nasty exceptions (which probably keeps the port open)
