Demand Peripherals     Robotics and Automation Made Easy

GPIO4: Quad General Purpose Input/Output Card

The Quad GPIO card gives direct access to four pins on the FPGA. Output is at 3.3 Volts and input can be either 3.3 or 5 Volts.

 

Features: - FPGA input, output, or bidirectional access - 3.3 or 5 Volt input - 3.3 Volt output - Pin headers or screw terminal connections

The GPIO4 card is a good choice for any of the following peripherals:
  - gpio4 : General Purpose I/O
  - ping4 : Quad Ping))) sensor interface
  - in4 : Quad binary input
  - out4 : Quad binary output
  - quad2 : Dual quadrature decoder
  - count4 : Quad event counter
  - pwmin4 : Quad PWM input
  - pwmout4 : Quad PWM output
  - ws28 : Quad WS2812 LED controller
  - servo4 : Quad 13-bit servo controller

The pin-header version has four three-pin headers for I/O and has screw terminals to set the voltages on pins 2 and 3. Separate power lines are handy if you want to power a servo or other circuit from the header.

 

Hardware:

The schematic and layout of the two GPIO4 cards are shown below. The Eagle schematic and board files for the pin-header version are available here: gpio4.sch and gpio4.brd. The Eagle schematic and board files for the screw terminal version are available here: gpio4.sch and gpio4.brd.

The bill-of-materials files are available here gpio4.txt and here gpio4-st.txt.