I was looking for a method to enter new phrases that would be displayed. With the 20x15 display everything was hard coded, this would not work with this display. I wanted to find a way to enter new phrases with a USB keyboard. The Arduino could not work directly with the USB keyboard. I found this device and ordered one.
This would communicate I2C with the arduino and I could order it with the USB keyboard profile already loaded, less work for me to do :D This worked great, at first I was using a USB keyboard that had a USB port on it, and the device would no recognize it. I then found a simple USB keyboard (no USB host ports on it) and it worked perfectly, this was also nice an inexpensive.
One important item I noted. I need to make sure I have a very strong mounting case to allow "Anyone" to connect the USB keyboard. I don't want people not familiar with the hardware to have to hold the devices to connect the USB keyboard. I need to mount this securely in a box. Now I can get input form a USB keyboard.
Features I need to add to support this.
1. I will have four "Phrases" being displayed in a rotating pattern. When I see "xxxx" I will know that new data is coming in. I will flash some LEDs, green, as a visual feed back to the operator.
2. Need to work out the buffer timing. The default "USB Host program" checks every 5 min. I need to create a buffer on the Arduino side, so I can handle not being spread across USB Host buffer.
3. Need visual feed back that each "phrase has been accepted".
4. Go back into display mode