GTT returning 254 253
Posted: Wed Nov 11, 2015 2:41 am
We have an app driving a GTT43A with v2.0 firmware. Everything runs fine for a couple of hours after openning the USB connection to the device when out-of-the-blue, the device returns [252, 253] following a command [254, 97, 0, 0, 240, 0, 0] (DisplayBitmap, buffer idx=0, X=240, Y=0). What does 252,253 mean? There's no mention of it in the protocol docs. There are other posts on this forum indicating that sending 254,253 to the device kicks the watchdog timer causing a reboot. I can't tell in my app if the 252,253 message directly follows the DisplayBitmap command or if it is being sent unsolicited (like an event). I'm guessing this indicates the internal watchdog timer has fired and the unit is rebooting. Can someone comment?
Associated with this problem is that at about this point, the display of bitmaps gets screwed up and when I try to draw a buffer, the image from a different buffer is shown on the screen. This all points to a firmware bug.
Thanks,
BC
Associated with this problem is that at about this point, the display of bitmaps gets screwed up and when I try to draw a buffer, the image from a different buffer is shown on the screen. This all points to a firmware bug.
Thanks,
BC