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simpleavr made a logic probe out of a TI EZ430 dongle for a 43oh.com contest:
this is a simple logic probe project based on TI EZ430 dongle. i took advantage of a free offer on a couple of ez430s from TI in september 2010. they are very handy and fun in trying out small code snippets and watch the led blink.
TI EZ430 EZProbe – [Link]
The 74LSxx chip family is a collection of discrete logic ICs, like logic gates, flip-flops, counters etc. But what are your options if you can’t find a specific 74LS chip? You can replace it using RDT-TTL5V-14 Programmable TTL digital logic gate. RDT-TTL5V-14 can be configured to any 74LS discrete logic gate function offered in a 14-pin DIP package footprint.
Programmable TTL digital logic gate - [Link]
I came across a very well designed USB Logic Analyzer made by Joe Garrison that sells for $149. This instrument is based on Cypress EZ-USB series chips and can help many electronics enthusiasts to debug their projects. The case is made from anodized aluminum and is laser etched. Windows software is really impressive also. Here are some key features:
- USB 2.0 With USB 2.0, Logic delivers sampling rates up to 24MHz @ 8 bits wide
- Uncompromised Design Logic is made of beautiful anodized aluminum
- The Best Wires Logic comes with color-coded, non-kinking, ultra-flexible 22AWG 65/40 patch cable
- The Best Probes Logic is equipped with E-Z-Hook XKM Micro-Hook probes for fast and secure connections
- Easy and Fast Set your sample rate (samples per second) and the number of samples to capture in a snap
- Readily Identified In addition to each input being color-coded, you can also type in a description of the input in particular
- Quick on the Trigger Logic has an optional 4-level trigger so that the software will start recording only when a sequence you specify is satisfied.
- … more
But the most interesting thing in this story is that Joe Garrison describes his journey to the final product in his blog, including many photos of the design and construction proccess. Check it out.
Saleae USB Logic Analyzer – [Link]
A logic analyzer is useful in electronic development and debugging, especially where fast logic circuits are involved with lots of signals whose relations have to be verified or examined. A logic analizer is a like a recorder for digital signals. During a certain (small) period of time, the state of a few digital lines can be recorded to a file. An event can be specified to signal the start of the recording, i.e. line 1 toggeling from 0 to 1. This recording can be viewed afterwards, allowing for zooming and scrolling in the time domain.
In this page a homebuilt logic analizer is presented.
A logic analyzer using the PC’s parallel port – [Link]
Today we are taking you one step deeper into a microchip than we usually go. We look at transistors and the logic functions they compose, which helps us understand custom ASICs now found in some secured processors.
To reverse-engineer the secret functionality of an ASIC, we identify logic blocks, map out the wiring between the blocks, and reconstruct the circuit diagram. Today, we’ll only be looking at the first step: reading logic.
Reverse-Engineering Custom Logic (Part 1) - [Link]
This page describes a very low cost logic analyser using an 18F2525 PIC microprocessor and a PC. The PIC is used as a hardware capture device which monitors the datalines and records all changes. The buffering, triggering, interpretation and display is handled by a PC program running under Windows. The hardware cost will vary between €15 (RS232 version) and € 30 (USB version). The analyser can operate in a “Fast Sampling” mode, in which the data is sampled into an internal 1K buffer on the PIC and in “Normal Sampling” or “Continious Sampling ” mode in which all data changes are offloaded to the PC in real time and arbritary sampling buffer size is available.
PicLA: a very low cost Logic Analyser - [Link]
This is a really cool logic probe that I must built one.It’s simple to build for hobbyist.Travis writes:
While my original probe is damned useful, it was a bit of a rushed job. Since then, I’ve found uncoated silver jewelry wire whose diameter is just a hair smaller than the inner diameter of the needle, allowing me to force it in for an electrical connection. More importantly, as I no longer solder to the outside of the needle, I can restore the safety cap and save my fingers from getting nicked.
Syringe Logic probe - [Link]
Atanua is a real-time logic simulator, designed to help in learning of basic boolean logic and electronics. It uses OpenGL hardware-accelerated rendering and a custom UI designed for a fast workflow and a very low learning curve, letting the students concentrate on learning the subject instead of spending time learning the tool.
See the interactive flash demo!
Atanua – Real-time logic simulator - [Link]
GALs are the simplest member of the programmable logic family that also includes CPLDs and FPGAs. They are the modern replacement for the one-time programmable PAL devices that were first introduced in the late 1970′s. Unlike PALs, GALs can be erased and reprogrammed many times. And unlike CPLDs and FPGAs, GALs don’t require using a hardware synthesis language like VHDL or Verilog, or any other special design tools. Although it’s possible to use fancier tools to configure GALs, the simplest method is just to write logic equations in a plain text file, defining each output in terms of the inputs. Run your equations through a command-line tool to create the binary GAL data, and you’re ready to go. Easy as pie! [via]
Getting started with GALs - [Link]
LogicSim is a java software that helps you simulate digital circuits. You can design and simulate digital logic circuits with logic gates like AND, OR, FlipFlop, etc. under almost all operational systems. You can create your own gates by saving a circuit as a “module” and reuse this module in another circuit.
The following types of logic gates are included:
- Basic: AND, NAND, OR, NOR, XOR (Antivalence), Equivalence, NOT
- Flip Flops: RS, D, T, JK, JKMS
- Timers: clock generator, MonoFlop, Turn on delay, Turn off delay
- Inputs: Switch, number-input for decimal and hexadecimal values
- Outputs: LED, LCD for decimal and hexadecimal values
LogicSim – Digital logic circuits simulator - [Link]
