1602 LCD screen 1602A module backlight blue on the white character type LCD1602A-5V LCD1602 | Электронные компоненты и

1602 LCD screen 1602A module backlight blue on the white character type LCD1602A-5V LCD1602 | Электронные компоненты и

1602 uses the standard 16-pin interface, where:

1st foot: VSS is ground power

2nd foot: VDD is connected to 5V power supply

3: V0 for the LCD contrast adjustment side, then the weakest contrast when the power supply, ground power when the highest contrast, the contrast is too high will produce "ghosting", you can use a 10K potentiometer to adjust the contrast

Step 4: RS is the register select, select the data register at high level, select the instruction register when the low level is selected.

5 feet: R / W read and write signal lines, high when the read operation, low when the write operation. When RS and RW are low together, the instruction or display address can be written. When RS is low, RW is busy and the busy signal can be read. When RS is high, RW can write data.

6 feet: E-side to enable the end, when the E-side from high to high, the LCD module to execute the command.

7 ~ 14 feet: D0 ~ D7 for the 8-bit two-way data lines.

15 feet: backlight power positive

16 feet: backlight power supply negative

1602 LCD module internal character memory (CGROM) has stored 160 different dot matrix character graphics, as shown in Table 1, these characters are: Arabic numerals, English letters of the case, commonly used symbols, and Japanese kana , Each character has a fixed code, such as the capital of the English letter "A" code is 01000001B (41H), the module shows the address 41H dot matrix graphic display, we can see the letter "A "

The following is the procedure for displaying the letter "A" at the position of the first character of the second line of the LCD module: ORG 0000H

RS EQU P3.7; determine the specific hardware connection
RW EQU P3.6; Determines how the specific hardware is connected
E EQU P3.5; determine the specific hardware connection

MOV P1, # 00000001B; clear screen and cursor reset
ACALL ENABLE; Calls the write command subroutine

MOV P1, # 00111000B; Set the display mode: 8-bit 2-line 5x7 dot matrix
ACALL ENABLE; Calls the write command subroutine

MOV P1, # 00001111B; The display is on and the cursor is on and the cursor is allowed to flash
ACALL ENABLE; Calls the write command subroutine

MOV P1, # 00000110B; text does not move, the cursor automatically move to the right
ACALL ENABLE; Calls the write command subroutine

MOV P1, # 0C0H; write display start address (second line first position)
ACALL ENABLE; Calls the write command subroutine

MOV P1, # 01000001B; letter A code

SETB RS; RS = 1
CLR RW; RW = 0; ready to write data
CLR E; E = 0; Execute the display command
ACALL DELAY; to determine whether the LCD module is busy?
SETB E; E = 1; display is complete, the program stops

AJMP $

ENABLE:
CLR RS; write subroutine of control commands
CLR RW
CLR E
ACALL DELAY
SETB E
RET

DELAY:
MOV P1, # 0FFH; determine whether the liquid crystal display is busy subroutine
CLR RS
SETB RW
CLR E
NOP
SETB E
JB P1.7, DELAY; If P1.7 is busy, it is busy waiting for it
RET

END

The program at the beginning of the LCD module function was initialized set, agreed to the display format. Note that when the characters are displayed when the cursor is automatically shifted to the right, without manual intervention, each input instructions are called to determine whether the LCD module is busy subroutine DELAY, and then enter the display location of the address 0C0H, and finally enter the characters to display A code 41H The

SMC1602A (16 * 2) Analog port wiring
Link diagram:
-------------------------------------------------- -
LCM ---- 51 | LCM ------51 | LCM ------ 51 |
------------------------------------------------ |
| DB0 ----- P1.0 | DB4 ----- P1.4 | RW ------- P2.0 |
| DB1 ----- P1.1 | DB5 ----- P1.5 | RS ------- P2.1 |
| DB2 ----- P1.2 | DB6 ----- P1.6 | E -------- P2.2 |
| DB3 ----- P1.3 | DB7 ----- P1.7 | VLCD Connect 1K Resistor to GND |
-------------------------------------------------- -

[Note: AT89S52 using 12M crystal]
================================================== =========== * /

#define LCM_RW P2_0 // define the pin
#define LCM_RS P2_1
#define LCM_E P2_2
#define LCM_Data P1
#define Busy 0x80 // is used to detect the Busy identity in the LCM status word

#i nclude

Void WriteDataLCM (unsigned char WDLCM);
Void WriteCommandLCM (unsigned char WCLCM, BuysC);
Unsigned char ReadDataLCM (void);
Unsigned char ReadStatusLCM (void);
Void LCMInit (void);
Void DisplayOneChar (unsigned char X, unsigned char Y, unsigned char DData);
Void DisplayListChar (unsigned char X, unsigned char Y, unsigned char code * DData);
Void Delay5Ms (void);
Void Delay400Ms (void);

Unsigned char code uctech [] = {"uctech"};
Unsigned char code net [] = {"uctech.icpcn.com"};

Void main (void)
{
Delay400Ms (); // start waiting, wait for LCM to talk about working status
LCMInit (); // LCM is initialized
Delay5Ms (); // delay for a moment (no)

DisplayListChar (0, 5, uctech);
DisplayListChar (0, 0, net);
ReadDataLCM (); // test sentence is meaningless
While (1);
}

// write data
Void WriteDataLCM (unsigned char WDLCM)
{
ReadStatusLCM (); // detect busy
LCM_Data = WDLCM;
LCM_RS = 1;
LCM_RW = 0;
LCM_E = 0; // If the crystal speed is too high, you can add a small delay after this
LCM_E = 0; // delay
LCM_E = 1;
}