How-to: Programmable Logic Devices (CPLD)

December 11, 2008 by Ian 57 Comments

Complex programmable logic devices (CPLDs) contain the building blocks for hundreds of 7400-serries logic ICs. Complete circuits can be designed on a PC and then uploaded to a CPLD for instant implementation. A microcontroller connected to a CPLD is like a microcontroller paired with a reprogrammable circuit board and a fully stocked electronics store.

At first we weren’t sure of the wide appeal and application of CPLDs in hobbyist projects, but we’ve been convinced. A custom logic device can eliminate days of reading datasheets, finding the ideal logic IC combination, and then waiting for chips to arrive. Circuit boards are simpler with CPLDs because a single chip with programmable pin placement can replace 100s of individual logic ICs. Circuit mistakes can be corrected by uploading a new design, rather than etching and stuffing a new circuit board. CPLDs are fast, with reaction times starting at 100MHz. Despite their extreme versatility, CPLDs are a mature technology with chips starting at $1.

We’ve got a home-etchable, self programming development board to get you started. Don’t worry, this board has a serial port interface for working with the CPLD, and doesn’t require a separate (usually parallel port) JTAG programmer.

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Parts: 1-Wire Temperature Sensor (DS1822)

December 10, 2008 by Ian 18 Comments

1wire

Download: buspirate.v0d.zip

Dallas/Maxim’s 1-Wire protocol is the most requested addition to the Bus Pirate. We finally got some 1-Wire parts, and today we’ll demonstrate the DS1822 1-Wire digital thermometer. Grab the datasheet (PDF) and follow along.

This post is accompanied by release v.0d of the Bus Pirate firmware for hardware version 0. This includes the new 1-Wire protocol library, more configuration options, and other improvements.

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Bus Pirate Firmware Update (v.0c), JTAG And More

December 1, 2008 by Ian 31 Comments

stat

Download: buspirate.v0c.zip

A few weeks ago we wrote about our Bus Pirate universal serial interface tool. We used the recent holiday to add some new features, like a JTAG programmer, macros, frequency measurement, and more. A major code reorganization makes everything easier to read and update.

Check out the a demonstration of the new features below. We’re compiling a roadmap and wish list, so share your ideas in the comments. You can also see how we used the Bus Pirate to read a smart card and test-drive an I2C crystal oscillator.

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Parts: 133MHz-16.2kHz Programmable Oscillator (DS1077)

November 28, 2008 by Ian 23 Comments

The DS1077 is a 5volt, 133MHz to 16kHz programmable clock source. The internal frequency divider is configured over a simple I2C interface, and the chip requires no external parts. Not bad for under $2. We used the Bus Pirate to test this chip before using it in a project. Grab the datasheet (PDF) and follow along. Continue reading “Parts: 133MHz-16.2kHz Programmable Oscillator (DS1077)” →

How-to: Read A FedEx Kinko’s Smart Card (SLE4442)

November 25, 2008 by Ian 27 Comments

Our wallets are filling up with SIM and RFID cards that contain hidden information. Using our latest project, the Bus Pirate universal serial interface, we can dump the memory from many common smart cards. In today’s How-to, we show you how to interface common smart cards, and walk you through the data stored on a FedEx Kinko’s prepaid value card.

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How-to: The Bus Pirate, Universal Serial Interface

November 19, 2008 by Ian 60 Comments

UPDATE: New firmware with JTAG and more

We’re always excited to get a new chip or SIM card to interface, but our enthusiasm is often dampened by the prototyping process. Interfacing any chip usually means breadboarding a circuit, writing code, and hauling out the programmer; maybe even a prototyping PCB.

A few years ago we built the first ‘Bus Pirate’, a universal bus interface that talks to most chips from a PC serial terminal. Several standard serial protocols are supported at 3.3-5volts, including I2C, SPI, and asynchronous serial. Additional ‘raw’ 2- and 3- wire libraries can interface almost any proprietary serial protocols. Since this has been such a useful tool for us, we cleaned up the code, documented the design, and released it here with specs, schematic, and source code.

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Gift Card Electronics

November 11, 2008 by Kimberly Lau 28 Comments

Gift-giving season is upon us, and it’s time for people to start panicking about what to give to their friends and families. Gift cards have gained in popularity over the years, as companies count on people to forget to use them. But how about gift cards that do more than store a token amount of cash? Best Buy is now selling a gift card that doubles as a speaker. It has a mini headphone jack that’ll plug into any audio player. You only need to spend fifteen dollars to get it. Target’s gone all out, with a gift card that is also a 1.2 MP digital camera. It comes with a USB cord and driver disk, and there’s even one with a 64MB USB flash drive. We’re very interested to see if these will take off, and what people will do with them once the cards are used up.

[via Gizmodo]