键盘由5个按钮 - 选择，向左，向上，向下和向右加一个RESET键。要保存数字IO引脚资源，键盘接口只使用一个ADC通道。密钥值是通过一个5级的电阻分压器读取。当按下一个键时，ADC通过读取分压器的电压值;然后将电压值与存储在数组中，以确定被按下的键的电压值的阈值。
The pin out for this dispay shield is as folows (display-arduino): D4-4, D5-5, D6-6, D7-7, RS-8, E-9.
Buttons have a nice click to them and are all (except reset) readable from pin A0 (schematic for how they are conected would be nice HK)
When pluged in to an arduino it interferes a bit with the power jack but not a whole lot, the board itself sticks about 1cm over the left edge of arduino.
I've tested this with arduino due which is 3,3V, the display works prfectly, the same cant be said for the buttons as they are powerd from 5V, some hardware hackong will be required.
Other than that it feels like a decent quality product, the soldering is ok, I'd like to see more solder in a couple of places, but over all good for the price.Excelente producto con buena calidadThe Arduino LCD screen is a backlit LCD screen with headers. You can draw text, images, and shapes to the screen with the LCD library. There is an onboard micro-SD card slot on the back of the screen that can, among other things, store bitmap images for the screen to display.Works well, is very easy to use... just plug in shield, and you're good to go! Hobbykings documentation could have been a bit better though.
Use LiquidCrystal lcd(8, 9, 4,5, 6, 7); in order to control the LCD, IO pin 10 to control the backlight (recommend you use pinMode(10,INPUT) to turn on, and pinMode(10,OUTPUT) to turn it off).
Only uses one analog pin (A0) for the five control buttons - you just need to work out the different voltages that you'll read when you press each button - which will vary slightly depending if powering Arduino from external power or USB. 6th button is linked to reset line.This is a cool little shield. Good price. I personally haven't found much use for it, but it was cool when I first got it up and running. I did a more in depth review at the address below.
aeronauticsroboticsandhotglue * blogspot * com/Very good component, the example software is downloadable in the files section. Very easy to use good contrast very cheap if compared with performancesFor the money you can't buy this and make it yourself. I'd put this on your must have list.
OlliW BLHeliBox over on HelifreaksVery good product , compatible with arduino LCD libraryMine works as advertised. If you do a google search on 'LCD keypad shield', the top returns are the pages for this device from therobotshop_dot_com. There are schematics and excellent code examples.
I have a couple of possible uses for mine - hopefully I can port the code from the 3DRobotics ground station. I also tested it with a 4 x 20 display that I have and it works too.
Very nice device at an extremely good price.
nice LCD pad shield, like other users have brought out, if you think it is broken, it aint, just change the contrast