Tag Archives: I2C

HOW-TO: Access Bus Pirate v4 on-board I2C EEPROM

Bus Pirate v4 has an on-board 24xx64 8Kbyte data storage chip called an  EEPROM (IC3). It can be used to store various settings and preferences, but cooler, the EEPROM’s I2C interface can be accessed from within the Bus Pirate’s I2C mode. First time users can get familiar with the Bus Pirate without any added components! […]

STM M24LR04E-R 4-Kbit dual interface EEPROM with RFID

STMicroelectronics has introduced the M24LR04E-R 4-Kbit Dual Interface EEPROM with RFID. “The M24LR04E-R device is a dual-interface, electrically erasable programmable memory (EEPROM). It features an I2C interface and can be operated from a VCC power supply. It is also a contactless memory powered by the received carrier electromagnetic wave. The M24LR04E-R is organized as 512 […]

Mini I2C OLED Display with just 4 connections

Joshua Jach has developed and released his mini I2C OLED display, a project fully funded via KickStarter. During the campaign, he shared insights on how integrating emerging technologies, including promising crypto advancements, could expand the project’s functionality, especially in secure data transmission. His OLED module provides a simple way to interface MCUs with a small […]

App note: Slave I2C communication and setup on PIC devices with MSSP modules

Here is an app note from Microchip describing how to setup, and implement slave I2C communication on Pic devices with MSSP modules. It also features assembler code for PIC18s and PIC16s. Many devices in the PICmicro family have a Synchronous Serial Port (SSP) or Master Synchronous Serial Port (MSSP). These peripherals can be used to […]

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 […]

Cheap 1.3” 96X68 monochrome LCDs with I2C interface

Greeeg tipped us of to some cheap $3 1.3” 96X68 monochrome LCDs. They have a solderable connector with a manageable pitch of 0.6mm. A simple I2C interface protocol is used to interface with these LCDs. These are Displays from ebay are small B/W displays from the nokia 1202 and a few other models. They do […]

App note: Opto-isolating the I2C bus

Isolation is important if you need to separate two circuits completely, leaving no possibility of an electrical problem in one causing an problem in the other. The most challenging digital circuits to isolate are bidirectional data lines like the I2C bus. In this EETimes editorial the opto-isolation of the I2C bus is covered in detail. […]

Alphanumeric “bubble-type” DL1414 LED I2C display driver

Paul made built an I2C driver for a 16-digit alphanumeric “bubble-type” display. He used four 4-digit DL1414 displays connected to a PCF8575 16bit I2C port expander and a 74138 logic IC. He was nice enough to provide the source files for his project. Via the forum.

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 […]

App note: Reading two bytes of data over I2C

Some I2C sensors and devices store more then one byte of data that needs to be read by a microcontroller. Many of these devices change the data once a stop bit has been received. Problems might occur if the data is read by the microcontroller in two consecutive 1byte transactions. If so, the microcontroller will […]

I2C controlled 4X4 RGB LED matrix

Mashiara designed an I2C controlled 4×4 RGB LED matrix. He uses 3 PCA9635 I2C-to-PWM drivers with 16 PWM outputs. Each IC controls a different basic color of the LEDs. The up-side to this design is that all of the drivers are on-board, and only control signals are needed to manipulate the matrix. The down side […]

App note: Software real time clock and calendar.

Here is an app note from Microchip that provides information on how to implement a real time clock and calendar on the PIC16f18xx series of microcontrollers. It uses an external 32.768KHz crystal that drives the Timer1 resource of the uC. The neat thing about a 32.768Khz clock source is that it can be divided by […]

Bus Pirate: Interfacing with the ChronoDot over the I2C

Paretech used his Bus Pirate in I2C mode to interface with the DS3231 real time clock located on the ChronoDot board. The DS3231 is a high precision real time clock IC with an integrated crystal. He documented his experience with both devices. All the resources needed to setup a I2C connection to a DS3231 are […]

Bus Pirate: Interfacing with an audio codec chip

Jared wrote about his experience interfacing the Bus Pirate with an audio codec chip using the I2C mode: It is no exaggeration to say the Bus Pirate saved me a metric crap-ton of time. In about ten minutes, I had the Bus Pirate hooked to the audio codec, figured out the text command interface, and […]

MLX90614ESF IR thermometer interface with the Bus Pirate V3 and V4

TitanMKD shared a demo of the MLX90614ESF IR thermometer interface with the Bus Pirate. His demo contains details on how to read the device specifications in the Bus Pirate I2C mode, ambient and measured object temperature, and PWM mode calibration data. Multiple measurements can be read every 100ms. Via the forum. Get your own handy Bus […]

I2C controled 8 relay driver switches plug-in devices

Megabug posted his I2C relay driver board for controlling 8 outputs. It controls 8 relay switches in which one pin of each switch is common, while the other pins are available through 8 screw type headers. It uses the PCA9554 8bit I2C port expander to drive a ULN2803A buffer which in return drives the relay coils. All buffer input […]

HH10D humidity sensor Bus Pirate interface

Anthony posted a tutorial on interfacing  HH10D humidity sensor with the Bus Pirate. He did the hard work of finding the calibration data, follow his tutorial and you’ll save time. HH10D uses a change in capacitance due to humidity to alter the output pin frequency. The calibration data is stored on a I2C EEPROM. Two modes of the Bus […]