PIC Projects
TFT Clock and Thermometer
WiFi, Ethernet
Doorbell with SD / EEPROM
SD FAT16/32 for .bmp
LCD TFT Egg Timer
LCD TFT Oscilloscope
SD Talking Clock
SD Sound Recorder,
    FAT32 wav Player
LED Thermometer
LED Egg Timer
LCD Egg Timer

Frequency Counters
100KHz For PC
1MHz For PC
8 Digits LED 50 MHz
Scope Screen Display
LCD Module 10MHz
6MHz for Android
USB PIC18F2550
USB TFT display BMP
USB DS18B20 Sensor
USB Thermometer
USB Counter
USB Meter
USB Oscilloscope
USB Input-Output
USB 16x2 LCD

COM & LPT Ports
MCP3201 on LPT
Serial TFT Text
Serial Inputs Outputs
Serial Port LCD
Analogue Signal to LPT
MCP3201 on Serial Port
Serial Thermometer
Analogue Signal to Serial
LCD Display on LPT
Serial Thermostat

Water Softener
HP Stream 7 docking
3.7V to 5V
Solar Charger

Infrared Decoder
PIC Music

Code Lock
Code Lock with LCD
HOME MOBILE Technical Tips


The serial port drives and powers an LCD module of 16X2 characters. Included a VB6 software, PIC C code and a circuit diagram. The communication is RS232 protocol. The VB application transmit only the last input byte to avoid overflow of the receive register of the PIC16F628A.
The serial port can source about 4 mA which is enough to drive the pic and the LCD module. The serial port can't power LCD with LED back light.
You can read more about serial interface in http://www.beyondlogic.org/spp/serial.htm

VB6 code, PIC code and circuit diagram download (20KB). You are free to use the circuit diagram and the VB software with no limitations.

The VB6 application.

Circuit Description
See also Technical Tips

Pin 4 at the serial port is turned to +12V by the software enabling RTS. It is regulated to 5V by 78L05. The 5V is the supply to the microcontroller.
Pin 3 is used to drive RX input, BC337 reverse the signal phase.

LCD display and driver has 14 way connector, 10 connections are used, 4 bits data bus is selected. There is a big selection of LCD modules, and they are very similar in characteristics i.e. DM1601, ACM1601.
Vss - Supply GRD.
Vdd - Supply 5V
Vo - Contrast Adjust
RS - Register Select
R/W - Data Read/Write
E - Enable
D4-D7 - Data Bus Lines
LCD module is 20K pot is the LCD contrast, make sure it is set.


Comments and questions

Copy the number from the picture It stops net-robots from adding comments.

11.05.2015 - 15:43
Name: Moty
Comment: Click button Download Software.

11.05.2015 - 15:01
Name: N
Comment: |All right, but where is the program or hex file for pic ????

21.11.2014 - 06:51
Name: ekraj
Comment: sir, I need voltage and current monitoring program using vb 6 and avr atmega32 plz help me

20.07.2014 - 13:04
Name: valera
Comment: good