Demand Peripherals             Robotics and Automation Made Easy

  

LCD6: Six Digit LCD Display

The LCD6 six digit LCD display card has six large, easy to read, 7-segment digits that are controlled by the LCD6 peripheral in the FPGA.

 

Features:
- Large, easy to read digits
- Hex display or segment control
- Uses the ESPI 7474 circuit for reliable operation
- User space Linux device driver (part of dpdaemon)
- Requires one slot on a Baseboard FPGA card

 

Hardware:

The LCD6 card drives the segments of the LCD using the putputs of a 749595 shift register. The clock to the shift registers uses the 7474 quadrature clock scheme from the ESPI card. Note that in the LCD6 card there are two data lines from FPGA and that one of the shift registers is clocked on the negative edge of the clock. Using two data lines and clocking on both edges lets the LCD shift registers fill in 8 clock cycles from the FPGA.

The schematic and layout of the LCD6 are shown below. The Eagle schematic and board files available here: lcd6.sch and lcd6.brd. The bill-of-materials is available here: lcd6.txt.