access point

Networking hardware which creates a local area network over Wifi

analog

In an electrical signal, existing in a continuous range, as opposed to the discrete ranges of digital. Sparkfun has a good writeup on analog versus digital if you want to learn more.

API

Application program interface: a set of tools and protocols which can be used to build software. In the case of Tessel, the hardware API is a library you can use to connect to modules, manipulate LEDs, and call out specific pins

CLI

Command line interface: a tool which lets you interact with a program (or in the case of Tessel, with the Tessel) via text-based commands in the command line, or terminal

communication protocols

Defined ways of communicating, e.g. a map between timed toggling of digital signals and hexadecimal values. Learn more in the Communication Protocols doc.

datasheet

A document of information about an electrical part or component. Typically, the manufacturer of an integrated circuit (IC) will provide a corresponding datasheet. Datasheets are usually available as PDF documents online, and can be found by searching for the part's number in a search engine.

DFU

device firmware upgrade, a mode of operation which allows for reprogramming of device firmware

digital

In an electrical signal, existing at discrete/binary values: on or off, zero or one. This can be used simply, e.g. on/off states of a switch or light, or you can toggle digital signals very quickly to encode complex messaging with communication protocols. Sparkfun has a good writeup on analog versus digital if you want to learn more.

GPIO

General purpose input and output: electrical pins which can be configured for various purposes

I2C

A hardware communication protocol which uses two wires: SCL and SDA. Read more about it in the Communication Protocols doc.

interrupt

An electrical signal which tells the processor that something needs immediate attention

LAN

Local area network

LED

Light-emitting diode

master

A machine or device directly controlling another machine or device

MDNS

Multicast domain name system, a way to map IPs to devices in a small network

MISO

Master input/slave output: in a SPI interface, the wire which carries commands to the controlling device from the device(s) under control

MOSI

Master output/slave input: in a SPI interface, the wire which carries commands from the controlling device to the device(s) under control

module port

A standard interface for connecting wires and modules to Tessel, configured as 10 "pins" or points of electrical connection

pins

Points of electrical connection with an integrated circuit

ports

Interfaces for electrical connections

pull-up

Ensures that given no input, the circuit assumes a defualt value, which is pulled high.

pull-down

Ensures that given no input, the circuit assumes a default value, which is pulled low.

PWM

Pulse-width modulation: a hardware communication protocol where there is a digital signal fluctuating between values at a set period, and the message is encoded by changing the percentage of that period in which the signal stays at one of the values. This can be used to approximate an analog signal on a pin which only supports digital signaling. A common application is in motor controllers, mapping a servo motor position to the percentage of the time a signal is held high

register

A register is a location in processor memory. Information in a register is stored in the form of digital (0 or 1) bytes. Typically, registers (and how each one can be used) are described in the datasheet of a part.

RX

Receive: the wire in a UART interface which receives data from the controlled device

SCK

Serial clock: the clock wire of a SPI interface, which ensures that the communicating hardware components are in sync and therefore able to understand each other

SCL

Serial clock line: the clock wire of an I2C interface, which ensures that the communicating hardware components are in sync and therefore able to understand each other

SDA

Serial data line: the data-carrying wire of an I2C interface

serial

See: UART

slave

A device or part of a device which is directly controlled by another

SPI

A hardware communication protocol which uses SCK, MISO, MOSI, and SS/CS (chip select) lines. Learn more in the Communication Protocols doc.

T2

Tessel 2

Tessel module

A piece of hardware built to interface with Tessel's module ports, paired with a software library

TX

Transmit: the wire in a UART interface which sends data to the controlled device

UART

Also referred to as serial. A communication protocol using the RX and TX lines. Learn more in the Communication Protocols doc.