I2C & Serial &keypad with 20x4 display
I2C & Serial 20x4 LCD Module With Keypad Controller
This is for one 20x4 display with controller (BV4618) attached to a 20x4 display
as shown. This controller has both I2C and Serial interfaces. Also there is a
connection for a 4x4 (or less) keypad. The controller is fitted and tested with
the device as shown, no soldering required.
Controller data sheet and resources
Size: 98 x 60 x 14
Viewing Area: 76 x 25.2
Character size: 2.95 x 4.75
The keypad is not supplied or fitted. However the membrane type
keypad is plug compatible also available in the shop.
Keypad not supplied.
This can form a complete user interface using either serial or I2C communication. It is user configurable
and set fo a 16x2 line display by default so two simple commands are used to set
it to 20 x 4.
Automatic scrolling takes place at the end of a line and also at the bottom of
the display freeing the host software form mundane tasks. The display as 3
interface options that are automatically selected when that interface is
1) Serial Interface
The serial interface has automatic Baud Rate selection form a set of pre-defined
Baud rates up to 115200. The selection is done on receiving the first character
that is carriage return (byte value 13 or \r). All bytes sent to the display
will be displayed and automatic scrolling takes place at the end of a line and
bottom of the screen. There is also a set of commands starting with ESC (byte
value 27) that are used to control the display such as clearing a line,
character positioning, clearing the display etc. Escape commands are also used
to input bytes from the keypad.
The controller will also accept input directly from a COM port and automatically
detect this. The interface is then the same as the serial interface.
3) I2C Interface
This option is automatically detected because the I2C data line has a pull up
resistor. The I2C address is user configurable in software and held in EEPROM.
Controlling the display is via commands in exactly the same way as the serial
There is provision for up to a 4x4 (16 key) keypad. The keypad is connected to the controller via the pads provided. There is also an interrupt output that will go low when there is any key in the
16 byte buffer and goes high when all the values have been removed from the
buffer. The host software need not monitor the controller constantly as any key
pressed will be captured by the controller for later access.
This is the controller that is fitted to the display. There are no pins on the
keypad interface but the serial and I2C interfaces are fitted with 90 degree pin
The controller works from 3V to 5V but this display requires 5V
- Serial Input and I2C input
- Automatic Baud rate from a selection of rates up to 112500
- Serial interface accepts RS232 input voltage levels
- I2C up to 400KHz
- VT100 superset
- Fully scrolling
- 65 byte input buffer
- 16 byte keypad buffer
- Max line length 80 char
- Max Lines 4
- keypad up to 16 switches (4x4)
- Supply voltage 5V DC
- Controller current: 6mA @ 4.7V
- Controller size: 55mm x 24mm
Compatible Products on the eBay Shop
|USB to I2C Convertor
||USB to I2C
What You Get
* LCD Display & Controller assembled and tested.
Also in the
BV4108 - Serial controller with an addressable interface
BV4308 - Serial controller with a VT100 interface - just send characters and
they will appear
BV4208 - An I2C version that also has a 3x4 keypad interface
BV4618 - A Serial and I2C (selectable) that has a 4x4 keypad interface.
All of the above also have kit options, i.e. not a fitted.