An Open Source Hardware Development Tool

LuxuryYacht writes "The PLAICE is an open source hardware and software project developing a powerful in-circuit development tool that combines in one device the features of a FLASH Programmer, Memory Emulator, and High Speed Multi-Channel Logic Analyzer. It runs uClinux. The logic analyzer features up to 200MHz sampling rates and up to 32 input channels. The logic analyzer Java client supports up to 200MHz sampling rates, user-controlled filtering operations, time line in diagrams, transfer rates, and user configurable drawing modes. The Java client supports access via almost any PC with a serial port and uses the RXTX serial library with support for 34 platforms including Linux, Windows, and Solaris. Java client plugins include an SPI and I2C bus protocol analyzer, conversion of timing analysis to state analysis, and post-processing functions."

That's nice

[tftp]

But logic analyzers are history. If you want to debug logic today you use ChipScope. That's not just because it is easier, but because breakout connectors (Mictor etc.) are expensive, large, and they disrupt the timing of the circuit.

As memory emulator this device may be useful sometimes, but many MCUs today come with internal RAM, and those that don't - they expect DDR2 speeds, and you can't emulate that.

This can be a full-featured Microblaze development system, though, with tons of samples. I think that's its best value. MicroBlaze was always poorly supported by Linux, as opposed to Nios (which Altera itself supports.) If we have, finally, a working [uc] Linux port to MB that alone is a great achievement. When I looked a year or two ago there was only one, non-functioning, port to a hardware that did not exist.

Re:That's nice

[evanbd]

History? Since when? I've been doing a bit of PIC microcontroller programming lately, and for debugging the various communications between a PIC and various peripherals this sounds perfect. I'll be seriously investigating getting one of these. Mostly the timing of such circuits isn't the issue, it's seeing the data actually on the channel without adding lots of debug code I don't have time or space for. This sounds like a great tool for the serious hobbyist.

Re:That's nice

[LuxuryYacht]

The logic analyzer design is targeted at debugging logic outside of the FPGA and the board itself. ChipScope is supported by the board for debug of logic inside the onboard Spartan-3E FPGA.

The memory emulator is currently targeted at FLASH devices.

Re:That's nice

[networkBoy]

You do realize that tektronix doesn't use mictor any more. They use compression probes that land on micro pads on your system board and are perfectly happy at DDR and DDR2 speeds.
LAs are alive and well. Your tools only work once the board is up and running, till then you still need to see raw I/O and such.
-nB

Re:That's nice

[c_oflynn]

I got a Logicport (500 MHz, 32 channel logic analyzer for $350) some time ago, and never looked back. I use it for FPGA designs where I want to capture a lot more data.

I always bring out some spare pins to a header, that becomes my debug port. Then you can route any internal signals to this header. Provided you're not trying to debug anything insanely high-speed, it works great.

It also supports the SPI/I2C/Serial decoding like this project. Only downside is the software is Windows only, and it uses USB so not sure how well it would work on Wine. I've got VMWare to run Windows though so don't mind.

  -Colin

Re:Huh...

[stewwy]

Well I can think of several uses in the HD=dvd and Bluray area :), and its nice that the code is available

Re:That's nice

[acarguy]

Well, logic analyzers aren't dead just yet. I work for Agilent (used to be HP), and we still make quite a few of 'em. Although the JTAG-based tools for internal FPGA logic analysis like Chip Scope are very useful and relatively inexpensive, they present some limitations (like consuming the internal block RAM of the chip) that traditional LAs don't have. Like anything, there are tradeoffs. Agilent has some tools that customize our logic analyzers to make internal FPGA measurements more easily and bridge the gap between the internal tools and the traditional LA. For example, we have a tool for MicroBlaze debug that lets you easily probe the internal MB signals and bring them out to an Agilent LA for trace, inverse assembly and correlation with the original source code. There is a tool called FPGA Dynamic Probe that works well for 'generic' logic debug as well. Traditional LAs can be very useful for tracking down the complex interactions between parts of designs implemented in FPGAs, discrete processors, memory systems and peripherals.