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11 years ago.
how to display a word in lpc11u24?
i load this program in my LPC11u24 but it won't display, can any one help
- include "mbed.h"
- include "TextLCD.h"
TextLCD lcd(p15, p16, p17, p18, p19, p20, TextLCD::LCD20x4); rs, e, d4-d7
int main() { lcd.printf("Hello World!\n"); }
2 Answers
11 years ago.
The above code should work,
TextLCD lcd(p10, p12, p15, p16, p29, p30); // rs, e, d4-d7
Asumming, you have connected up the screen correctly, Although, some LCD's need D0..3 set to logic levels, ... (LO, LO, LO, HI)
But most importantly, almost all 'older' LCD's will not work from 3V3, from MBED.
you can try connecting the supply for the LCD to USB 5Volts (pin 39 on MBED)
on an old board I have the connections are:
| pin | use |
|---|---|
| 1 | Gnd |
| 2 | 5V0 |
| 3 | V-LCD |
| 4 | rs |
| 5 | R/W |
| 6 | E |
| 7 | D0 |
| 8 | D1 |
| 9 | D2 |
| 10 | D3 |
| 11 | D4 |
| 12 | D5 |
| 13 | D6 |
| 14 | D7 |
| 15 | LED + |
| 16 | LED - |
11 years ago.
If there is enough voltage (5 Volts) then a dark line of pixels will be displayed, for the first 1/2 of the display,
Some displays need a negitive voltage on V-LCD.
what is the part number of the display, eg from farnell.
also show 'us' your connections ...
Lex
We cannot magically know what is wrong with it without a proper description: What did you make, how did you connect it, and which results do you observe.
posted by Erik - 22 Nov 2013