VOISS - GPIO
Written by Rich Morin.
Precis: an overview of VOISS (etc) GPIO handling
Note: As of early 2020, the VOISS project and F123Light were discontinued. For details, see VOISS - Status.
The Raspberry Pi had several connectors for standardized electrical interfaces, as discussed in VOISS - Interfaces. These include Ethernet, stereo audio output, USB, and video I/O. However, it also provides a 40-pin digital connector for the general-purpose input/output (GPIO) interface.
The pins can be used to accept and/or provide both power and digital signals. Although there is no provision for analog input, the output from a digital pulse-code modulation (PCM) signal can be integrated (using a capacitor) to provide analog (e.g., audio) output. GPIO pins can also be used to receive and/or transmit radio signals; see software-defined radio for details.
The pins in the GPIO connector are laid out in two closely spaced (0.1”) rows. It’s quite possible to connect single-wire jumpers to individual pins, but counting pins (to determine the correct position) can be a hassle. So, I’d suggest getting and using some of the available alternatives.
- cable edge marking (tactile, visual)
- pin numbering
- bump, notch, etc.
- jumper wires
- seeed grove