LCD TFT FREQUENCY COUNTER
Updated on 28.12.2019.
LCD TFT is digital display at its best, it displays versatile clear picture. The picture is built by entering the address and the color of a pixel or rectangle, so it's simple to use too.
Counter using PIC16F876A or PIC16F690. Included C code and circuit diagram. The LCD TFT module is a 1.8" 128 X160 pixel. The LCD is driven by SPI.
The frequency is displayed by 7 digits with leading zeros removed down to 1 digit. The picture displayed is based on 7 segment
for the PIC16F876A and universal text for the PIC16F690. The period is calculated. When input frequency is less than 1000Hz the period is displayed in us.
The counting is over a period of 1 second, generated by the 8/16 MHz crystal oscillator. The max counting is 7 digits
(10MHz). I tested the counter at up to 2MHz. Period of 1 sec is generated by TMR1 and CCP1.
LCD TFT modules vary depending on the drive IC. The module in the project has the driver ST7735, I bought this module directly from China because the price was more sensible.
Code is for MPLAB, MPLABX and compilers HI TECH or XC8
You are free to use the circuit diagram and the software with no limitations.
See also Technical Tips
Supply is 5V +/-10%.
Frequency input signal is TTL
levels, 5V max.
The TFT module has the driver ic ST7735, The inputs of the ic tolerate 5V,
one source is: