App note: Microcontroller-based serial port interface (SPI®) boot circuit

Simple circuit for sending command upon boot to the target device sortof boostraping hardware tachnique, an app note from Analog Devices. Link here (PDF) This application note describes the operation of a general purpose, microcontroller-based Serial Port Interface (SPI) boot circuit. This is a low cost solution for users who need to modify some of […]

Talk SPI to EEPROM part3: Test SPI Protocol with Bus Pirate

Jan Cumps tested out SPI Protocol using a Bus Pirate: It wasn’t my initial intention to use the Bus Pirate. But my first naive attempts to talk from Hercules to EEPROM failed. I could create the SPI instructions with the LaunchPad, but I didn’t get a reply back from the 25LC256. It’s in these cases that […]

Better SPI Bus design in 3 steps

Paul over at Dorkbotpdx has written an article on 3 steps to good SPI Bus design: A much better SPI bus design can prevent conflicts. 3 simple improvements are needed: Use pullup resistors on all chip select signals. Verify tri-state behavior on MISO: use a tri-state buffer chip if necessary. Protect bus access with SPI.beginTransaction(settings) and SPI.endTransaction().

Standalone SPI 7-segment display

Spacewrench over at Dorkbotpdx writes: I had some spare 4-digit 7-segment LED displays and some AT90USB82s, and I’d always intended to do something with them. This was probably the easiest thing! It’s just the AT90 driving the display, with a(t least) 4 wires controlling it: Vcc, GND, MOSI and SCK. (I haven’t written the code yet, […]

SPI Transactions in Arduino

Paul over at DorkbotPDX writes: For the last several weeks, I’ve been working on SPI transactions for Arduino’s SPI library, to solve conflicts that sometimes occur between multiple SPI devices when using SPI from interrupts and/or different SPI settings. To explain, a picture is worth 1000 works. In this screenshot, loop() repetitively sends 2 bytes, where […]

App note: Interfacing FT2232H hi-speed devices to SPI bus

Simplify USB to SPI connectivity by using this app note from FTDI. The FT2232H and FT4232H are the FTDI’s first USB 2.0 Hi-Speed (480Mbits/s) USB to UART/FIFO ICs. They also have the capability of being configured in a variety of serial interfaces using the internal MPSSE (Multi-Protocol Synchronous Serial Engine). This application note introduces the […]

Bus Pirate script to recover bricked radio

Koolatron over at the Bitcraze forum  re-program the Crazyradio over SPI using the BusPirate and this script, available at github:  I’ve knocked together a perl script to reflash a busted crazyradio over SPI using a Bus Pirate. This saved me from a firmware upgrade gone bad. Get an assembled Bus Pirate for $30, including world-wide shipping. Also available from our […]

7 segment display controlled by simple SPI interface

Touch let us know about these 4 digit SPI controlled 7 segment displays that cost a little less then $1 a piece. They include decimal separators and a colon separator so it’s easy to display time. I picked up some cheap 4 digit 7 segment displays over on eBay for $10 + shipping. They Include […]

NEW PROTOTYPE: 1.8″ TFT display with USB interface

Like so many others, we found a nice 1.8″ TFT display in China, and we decided to make a breakout for it. Instead of just breaking out the pins, and perhaps adding the micro SD card holder, we equipped our version with an USB enabled microcontroller and a few buttons for GUI projects. This display […]

App note: Common IC interface problems

A somewhat humorous app note describing the common IC interface protocols like I2C, SPI, and GPIO. Also covered are some problem with these interfaces that turn happy faces to sad. How can an interface change a happy face to a sad face? Engineers have happy faces when an interface works properly. Sad faces indicate failure […]

Interfacing the LTC2440 24bit ADC with the Arduino

Jbeale shows how to interface the LTC2440 24bit analog to digital converter with the Arduino. He provided the pin connections, a small sketch, as well as some advice to get it up and running. I should add: to reach the specified noise performance of this part (200 nV RMS) you must have an absolutely clean […]

Dual 4 digit 7-segment display board with SPI interface

Raj built a dual, 7-segment, display board with SPI interface. The board is based around the MAX7219 8x 7-segment display driver, which receives commands over SPI, and drives the display accordingly. The new display features eight 7-segment displays arranged in two rows of four digits. The on-board MAX7219 driver enables you to easily add eight […]

Problems with long cables and common solutions demonstrated

Bertho was inspired by a recent forum discussion about driving SPI signals over long cables, so he headed to the workshop and did some test. His epic analysis of transmission lines shows real life example of how signals degrade in cables of various lengths, and how to tackle some of the problems associated with transmission […]

App note: Using hardware SPI on XMEGA microcontrollers

Here is an app note from Atmel describing hoe to use the SPI module on their XMEGA microcontrollers. Also provided are source code examples for implementing both interrupt driven SPI communication and the polled method for slave and master devices. SPI is a full duplex interface, and at a low cost enabling high-speed communication between […]

App note: PSoC I2C to SPI bridge.

Here is an app note from Cypress that describes how to implement a I2C to SPI bridge on a PSoC IC. PSoCs are devices that incorporate a microcontroller, a logical gate array, and some analog peripherals. What makes them different than microcontrollers is that all the peripherals are separated from the microcontroller. They can function […]