![Arduino Uno REV3 [A000066]](https://images-na.ssl-images-amazon.com/images/I/61AvdQOxFzL._AC_UL116_SR116,116_.jpg)
Despite the Arduino focused listing title, the display is Hitachi compatible using the PCF8574T (in my unit) I2C converter backpack that can work on other processor lines easily. I needed to hook it up to a Cypress PSoc 5LP eval board (CY8CKIT-059). Cypress provides many code examples and auto-generates APIs for library parts like parallel and serial graphics and text displays. The library worked fine with the parallel Hitachi displays including this 4x20. It did not work with this backpack and the I2C library supporting NXP PCF2119x commands. The solution was to find and use a community library (V2.1 as of this date). It also adds a few new functions to integrate position and string and char printing. The default address (no jumpers installed on A0-A2) is 0x27 (7bit), or 0x4E (8bit). The non T version of the PCF8574 may be 3F default. You need to pay attention to the header or library component address entry for which form of address, 7 or 8 bit, is required to be entered as the protocol shifts the address 1 bit position. It is also helpful to run a small routine to scan the I2C bus to see what shows up if yo have any difficulty. Check for the community code at the cypress community website, thread number 11727. The backpack is a common part and you can remove it and use it on other displays, in my case a 2x16 Hitachi compatible display. For a programmable backlight level I cut the trace on the 5V side (top side of board) of the backlight 2 pin header and wired a jumper from the now open pin up to pin 16 on the backpack. My PWM wire supplies 5V and switched ground on a 2 pin 0.100" center plug. I changed it on the backpack so it would work on any display it ever got moved to since not all displays have easy onboard backlight connections or configuration jumper pads.
| Standing screen display size | 1 Centimeters |
|---|---|
| Screen Resolution | 2560 x 1600 pixels |
| Max Screen Resolution | 2560 x 1600 pixels |
| Processor | 210 |
| Card Description | Dedicated |
| Wireless Type | 802.11b |
