Product Info

This display/keypad/keyboard interface module includes a 4-row by 20-character LCD with a yellow LED backlight. A contrast control pot is provided for the LCD, an 8-pin connector for an optional 4x4 matrix keypad, and a PS/2-style keyboard connector. A prototyping area is provided for the addition of user application circuit components beneath the LCD, if desired. A 50-pin interface connector is provided, making it easy to interface to Adapt11 and Adapt12 products. The connector has a mirror-image pinout, and is meant for back-to-back stacking, planar, backplane, or ribbon cable interconnection schemes with any Adapt11, Adapt12 or Adapt9S12 MCU module. Other families, such as NanoCore12, MicroStamp11, MicroCore-11, and neCore12 can be accommodated. Click on the Details tab, above.

What you get:

• this product ships with hardcopy data sheet and schematic diagram
• data sheets, manuals, and all other resources for this product can be found by clicking on the Resources tab.

Product Details

The display is interfaced via a 74HC595 serial-to-parallel shift register to the SPI port of the MCU, with a couple of extra I/O pins being used for display reset and enable functions. Example code is available for several of our microcontroller boards.

Both PS/2 and AT-style keyboards are supported via appropriate connectors (only PS/2 connector populated). Interfacing these keyboards can be achieved via a couple of I/O pins and some simple code.

Support for a matrix keypad scanned via 4 outputs and read via 4 inputs is provided, by way of pullup resistors on the rows. Diodes comprise an ORing circuit so that an "any-key-pressed" signal is generated, which can be connected to an MCU interrupt pin. Some sample software to implement keypad scanning is available.

Provision is also made for a small audio transducer, by way of an optional general-purpose NPN transistor which can be toggled on and off via software to create various tones.

A prototyping area is included for your application circuitry, or for mounting MicroCore-11, MicroStamp11, or NanoCore12 modules directly onto the board.

The "rear-facing" design suits applications where the MCU module is to be mounted directly to the back of the display module, or the DKKI can be inserted in a backplane, or plugged together with an "Adapt" style MCU card in a planar configuration; hence, the mirror-image pinout of the 50-pin I/O connector.

Note: A stacked or backplane arrangement may not work with Adapt11EVBU, and some Adapt12 and Adapt9S12 families of cards due to mechanical interference between some of the connectors. However, a planar arrangement is practical.

Resources

• Data and Pinout Sheet
• Mechanical Drawing
• Adapt Family Application Card Pinout Table
• LCD data sheet
• Hitachi HD44780 LCD controller chip data sheet
• Thorough discussion of how to interface a PC keyboard
• Support Library (example code, app notes, docs)