User`s manual

ENDAT-K1001 USERS MANUAL

UNICORN COMPUTER CORP.

2-7.LCD Brightness Control

1) Inverter Brightness Digital level select:

LCDBK1: Inverter Header (2x3 with 2.0mm)

Pin No. Function Pin No. Function

VBL

INV-BRT

BKL ON/OFF

GND

2) Brightness Control port address:

This is alternate function with VBIOS (VESA) to offering an easy way to control

the LCD backlight ON and OFF as need. Please follow the instructions of

below for more detail in operation.

Sample code for brightness control (using Turbo C/C++ 3.0):

#define input_port 0xf40

outportb(0x2e,0x87); // Unlock register

outportb(0x2e,0x01); // Unlock register

outportb(0x2e,0x55); // Unlock register

outportb(0x2e,0x07); // Set Logic Device number pointer

outportb(0x2f,0x07); // Set Logic Device number

outportb(0x2e,0x25); // Set Multi-Function Pin for GPIO Set1

outportb(0x2f,0x0F); // GP10~17 (Default 01)

outportb(0x2e,0x2A);

outportb(0x2f,0x0F); // Set Bit 1: GPIO / 0:PCIRST

outportb(0x2e,0xC0); // Set Enable Simple GPIO

outportb(0x2f,0x0F); // GP10~17 (Default 01)

outportb(0x2e,0xB0); // Set GPIO Pin Polarity

outportb(0x2f,0x07); // GP10~17(Default 00) 1:Inverting/0: Non-Inverting

outportb(0x2e,0xC8); // Set GPIO Input Mode / Output Mode

outportb(0x2f,0x07); // 0: Inputer ; 1: Output

outportb(0xf40,0xnn); // Set active register is IO Base Address 0F40 “default 30”

// ; 0f40 = 30h  Out +0V / 0f40 = 38h  Out +5V

// ; 0f40 = 39h  Out +2.54V / f40 = 3Ah  Out +1.73V

// ; 0f40 = 3bh  Out +1.29V / f40 = 3ch  Out +1.04V

// ; 0f40 = 3dh  Out +0.86V / f40 = 3eh  Out +0.74V

// ; f40 = 3fh  Out +0.65V

Bit No 7 6 5 4 3 2 1 0

Map

NA NA NA NA P13 P12 P11 P10