Pinning LCD display 1601A:
| Pin no. | Symbol | Function |
|---|---|---|
| 1 | Vss | GND |
| 2 | Vdd | + 5V |
| 3 | Vo | Contrast Adjustment |
| 4 | RS | H/L Register select signal |
| 5 | RW | H/L Read/write signal |
| 6 | E | H->L Enable signal |
| 7 | DB0 | H/L Data bus line |
| 8 | DB1 | H/L Data bus line |
| 9 | DB2 | H/L Data bus line |
| 10 | DB3 | H/L Data bus line |
| 11 | DB4 | H/L Data bus line |
| 12 | DB5 | H/L Data bus line |
| 13 | DB6 | H/L Data bus line |
| 14 | DB7 | H/L Data bus line |
| 15 | A | 4.2 Volt for LED |
| 16 | K | Power for supply B/L (0V) |
The CFAH1601AYYBJP is an LCD display with 5×8 character-dot space and 16 character positions and LED (yellow) backlite. It has an industry-standard HD44780 compatible controller chip on the back. An 8-bit or 4-bit parallel interface, and a very wide viewing angle. It operates on +5 Volt, and consumes only 1.2 mA which makes it good for battery usage, but the backlite-LED uses 130 [email protected], so make e.g. a button which activates the backlite, and then automatically let it switch off after three seconds. What also can be done with this display is making your own characters (up to 8 max. by internal RAM, called CGRAM = Character Generator RAM) The ROM consists of the complete ASCII character-set, and also the Japanese/Greek characters, a total of 192 character locations. When using the 4bit interface, you must transmit 2 * 4-bit for each instruction. To let the display operate, it first must be initialized (init procedure) (don’t forget to adjust the contrast (0.8V), else you won’t see nothing. Use a 10k potmeter) I will show both 4- and 8-bit interfaces. 4-bit because it saves 4 i/o’s of the microcontroller. 8-bit because it’s shorter code. Here all features this LCD has:
- Interface with either 4-bit or 8-bit microcontroller.
- Character generator ROM: 192 different 5 x 8 dot-matrix character patterns.
- Character generator RAM: 8 different user programmed 5 x 8 dotmatrix patterns.
- Display data ROM and character generator RAM may be accessed by the microcontroller.
- Numerous instructions: Clear Display, Cursor Home, Display ON/OFF, Cursor ON/OFF, Blink Character, Cursor Shift, Display Shift.
- Built-in reset circuit is triggered at power ON.
- Built-in oscillator (270 kHz)
Next a diagram (4-bit interface) of a CFAH1601AYYBJP LCD display connected to an AT90S1200 microcontroller:
1x AT90S1200
1x 1×16 LCD (HD44780)
1x 78L05
1x 4 MHz resonator
1x 47uF/16V
2x 100n multilayer
1x 100n MKH
1x 10k pot
1x 10k
For more detail: Pinning LCD display 1601 using microcontroller
