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Messages - steamraven

1
Open Bench Logic Sniffer / Re: Advanced Triggers
Ian, thanks for that. It definitely  seems easier to let the user figure out the topology and just provide a UI, but it would be really cool just to type a boolean function and it figures it out for you. I was hoping someone here had some experience in synthesis algos to point me in the right direction.
2
Open Bench Logic Sniffer / Re: Advanced Triggers
Yeah, I read through the documentation, and it is very good.  It explains the configuration in detail, however, there is still the problem of mapping an arbitrary boolean function into a configuation for the trigger sums:

Example (A or (B and TIM1))

One mapping (of many) would be A -> A,  B-> E, TIM1 to TIM1

Code: [Select]
A---|                  
    A -------------|
B---|              |
                  |
C------|          |
      0-----------|
Edge1--|          |
                  |--------OR--------|
D----------|      |                  |
          0-------|                  OR---------------------------- output
Range1-----|      |                  |
                  |                  |
E(B)-------|      |                  (0 from other mid lut)
          AND -----|
Tim1-------|

It basically is a synthisis problem: how do I configure a base circuit G such that for all inputs, G is equivalent to a function F?

I have looked into using boolean satisfiability for logic synthesis, and this works if you only have like 4 inputs, but when you get to the full 16 inputs, the problem is has over 2^16 terms solving for 2^100 configuration bits. not fun.

Once I have this mapping, I can use dogbody's info to upload into the OLS
5
Open Bench Logic Sniffer / Advanced Triggers
While Jawi is working hard in his spare time to implement advanced triggers in his client, I wanted to discuss some of the technical details.

Given a boolean equation:  A or (B and TIM1)

how can we map this to the trigger sums in the advanced trigger? This seems very similar to FPGA synthesis.  Does anyone have any pointers for me on where to look for more information?

Thanks,

Matt
6
Open Bench Logic Sniffer / Trigger State Machine
I want to try my hand at VHDL and create a full state machine for complex triggers. I wanted to document it here so I can (hopefully) get some feedback and maybe help some people.

First, the Goal:
To create a full state machine with transitions controlled by internal triggers and external trigger while maintaining compatibility with the sump protocol and operation.


To start I will list the sump operation that I need to maintain.  This is mainly from what I see in the code. If there are other constraints, please let me know. I am not changing how the triggers detect conditions, just what they do when found.  Thus I will not describe serial vs complex and demux and such. These will stay the same.

Internal Triggers (4)
  Trigger can either immediately start capture or upgrade trigger level by 1
  Trigger can optionally delay for a certain number of clock cycles
    After delay, trigger either starts capture or upgrades trigger level by 1
    There is no check of continuing trigger condition
  Triggers are not retriggerable
    trigger is "armed" one cycle after ARM goes high
    trigger goes to off state after signaling and stays off until ARM goes high
  Trigger signals 1 cycle after trigger condition
  Trigger only signals if trigger level is equal to or greater than configured level

  Defaults:
    0 delay
    Match (upgrade level) not start
    trigger on level 0 and higher

External Trigger
  Immediately initiates run


Trigger State
  4 trigger levels (0 - 3)
    level 0 on arm
    level goes up by 1 on match from internal triggers
    level rolls over after 3

  1 run level.

Sump protocol
  set trigger config
    delay
    trigger level
    channel for serial (Not needed)
    serial flag (not needed)
    start flag

So I want my design to maintain the above behavior, especially the configuration commands.

More to follow....
7
Open Bench Logic Sniffer / Re: Timed Triggers
I wanted to try my hand at some VHDL and thought about trying to add a full state machine to the complex triggers.

Is this of actual interest to anybody here?

Matt
9
Open Bench Logic Sniffer / demux flag?
I was looking through the VHDL and came across the demux flag.  I couldn't find much in the docs or a way of setting it in the interface. Can someone give me some hints?

Thanks,
Matt
10
Open Bench Logic Sniffer / Re: Timed Triggers
I think I can do what I want with serial triggers.  So I can check for a high of up to 31 samples.

Mask:      11111111111111111111111111111111
value       01111111111111111111111111111111

Unfortunately, I cannot make use of the next levels.

It would be nice if you could specify more of a state machine for the triggers.
11
Open Bench Logic Sniffer / Timed Triggers
I have a signal that goes high and low quite a bit.  I am looking for a way to trigger if this signal stays high for a length of time, say 1 ms.

I see there is a delay setting in complex triggers and the protocol docs say
"delay: If a match occures, the action of the stage is delayed by the given number of samples"

But i am still confused how to use it for what I want. Any ideas?
12
Open Bench Logic Sniffer / Re: Test package: New SPI routing, Winbond ROM support
[quote author="wayoda"]

does all communication now happens over the DataFlash SPI-breakout pins on the pcb? That would make it quite easy to control the OLS from some custom SPI-Master hardware. (OLS run on batteries, with wireless network access? You can't buy that anywhere on this planet I think!)

[/quote]

Couldn't you also use the extra UART on the PIC?  I believe it is brought to a header. You would need a custom pic firmware, but might be easier than tapping the pins on the PIC.

Matt
13
Open Bench Logic Sniffer / Re: OLS Availability
Thanks for the quick reply. Since they are getting some in soon, I'll just go ahead and order.

I look forward to playing with it.  Regarding the papillo, I think having the LAX being synced to the OLS would be very beneficial. I for one am primarily looking for a logic analyzer, but I would definably pay more, if I could also get a nice FPGA development board.

Thanks for all the hard work in making this possible!

Matt
14
Open Bench Logic Sniffer / OLS Availability
I just discovered this project and I am very excited about an open source analyzer.  However, seeed (and their distributers) seems to be out of stock.  Where else can I get one of these?
Are there different revisions? What is the current revision?

I also noticed there is a logic analyzer project (lax) at gadget factory that runs on the papillo one (butterfly one) boards.  How different is this from the OLS codebase?

Cheers,
Matt

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