text-lcd-8x2
gabbapeople/electricity-meter/text-lcd-8x2
Drives a text 8x2 LCD screen with HD44780 chip
text-lcd-8x2
@/text-lcd-8x2
Drives a text 8x2 LCD screen with HD44780 chip
RSport
Board GPIO port with LCD RS pin
ENport
Board GPIO port with LCD EN pin
D4port
Board GPIO port with LCD D4 pin
D5port
Board GPIO port with LCD D5 pin
D6port
Board GPIO port with LCD D6 pin
D7port
Board GPIO port with LCD D7 pin
L1string
Text for the first line
L2string
Text for the second line
UPDpulse
Triggers new write
DONEpulse
Fires when write is done
C++ implementation
{{#global}}
#include <LiquidCrystal.h>
{{/global}}
struct State {
LiquidCrystal* lcd;
};
{{ GENERATED_CODE }}
void printLine(LiquidCrystal* lcd, uint8_t lineIndex, XString str) {
lcd->setCursor(0, lineIndex);
uint8_t whitespace = 8;
for (auto it = str->iterate(); it; ++it, --whitespace)
lcd->write(*it);
// Clear the rest of the line
while (whitespace--)
lcd->write(' ');
}
void evaluate(Context ctx) {
if (!isInputDirty<input_UPD>(ctx))
return;
State* state = getState(ctx);
auto lcd = state->lcd;
if (!state->lcd) {
state->lcd = lcd = new LiquidCrystal(
(int)getValue<input_RS>(ctx),
(int)getValue<input_EN>(ctx),
(int)getValue<input_D4>(ctx),
(int)getValue<input_D5>(ctx),
(int)getValue<input_D6>(ctx),
(int)getValue<input_D7>(ctx));
lcd->begin(8, 2);
}
printLine(lcd, 0, getValue<input_L1>(ctx));
printLine(lcd, 1, getValue<input_L2>(ctx));
emitValue<output_DONE>(ctx, 1);
}