Spark Fun serial LCD back light controlls.

Using Arduino Displays
1

Serial Enabled 16x2 LCD - White on Black 3.3V
sku: LCD-09067

Arduino MEGA 2560 R3

I am quite new at this, but been reading and searching quite a bit to avoid asking frivolous questions, but I need some advice.

I have this display working using this code:

#include <SoftwareSerial.h>

SoftwareSerial mySerial(9, 10); // mySerial(rx, tx);

void setup()
{
mySerial.begin(9600);

}

void loop()
{

mySerial.print(" Hello dave");
delay(2000);
mySerial.write(0xFE);
mySerial.write(0x01);
mySerial.print(" Got the serial");
delay(2000);
mySerial.write(0xFE);
mySerial.write(0x01);
mySerial.print(" working ");
delay(2000);
mySerial.write(0xFE);
mySerial.write(0x01);
delay(2000);

}

And I find this in the files associated with the serial controller for the LCD:

brightness_setting = letter & 0b.0001.1111; //Brightness is a value from 0-29 only (5-bit)
onboard_eewrite(brightness_setting, LCD_BRIGHTNESS_SETTING); //Record to EEPROM

along with Quite a few other similar lines pertaining to brightness controll.
according to the spark fun spec sheet on the 16f688, it requires a command :

by sending special command character 0x7C (decimal 124) followed by a number 128-157, the backlight PWM will be set.

So, my question is what does that look like on the scetch pad? I have tries several combinations of these commands and "|" characters follower by numbers and nothing works. I think i am missunderstanding the spec sheets due to my lack of knowlage so advice would be greatly apriciated!
Thanks

2

mySerial.write(0x7C);
mySerial.write(0x80);This should set the.back light to some brightness.

3

liudr:
mySerial.write(0x7C);
mySerial.write(0x80);This should set the.back light to some brightness.

that sequence will set the brightness to zero!

0x7C 0x80 // brightness off
0x7C 0x8C // 40%
0x7C 0x96 // 73%
0x7C 0x9D // 100%

other values in between to set different levels

here are some more commands that you might find useful

0xFE	254			
		0x80	address	cursor position
				
0x7C	124			
		1		backlight on
		2		backlight off
		3		set 20 chars per line
		4		set 16 chars per line
		5		set 4 lines
		6		set 2 lines
		7		set 1 line
		8		init LCD
		9		toggle splash
		10		set splash
		11		set 2400 baud
		12		set 4800 baud
		13		set 9600 baud
		14		set 14400 baud
		15		set 19200 baud
		16		set 38400 baud
				
0x08	8			backspace
				
0x12	18			set 9600 baud if received during splash
4

Thanks, got it 8)