Topic: triggering a data capture on FMC104  (Read 10250 times)

KevinNIST June 10, 2014, 10:36 AM

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Hi,
I want to use an FMC104 as a waveform digitizer with a programmable trigger. Is there a way to do this with the standard ML605 Board Support Package? Or, has 4DSP developed other firmware & software tools that can be shared?
I simplified explanation... on a rising edge, I want the ML605 to generate an interrupt to the host PC and buffer 10 microseconds of data. In response, the host PC would Save16BitArrayToFile and download the buffered data. After the download is finished, return to the original state.[/font]
This seems like a simple function that many customers would want to do. Perhaps 4DSP has done this already? Looking over the BSP, I don't see any interrupt & response routines in the C++ code. Can you offer some help and/or advice?[/font]

Thanks,[/font]
-Kevin
 

arnaudNL June 10, 2014, 11:24 AM (#1)

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Dear Kevin,


Our PCI API has a function called _4FM_ReadMailbox() which is blocking and wait a mailbox value to be received by the firmware. To be more precise, the function waits a value to be present in a software queue implemented in the device driver up to a given timeout value. When a mailbox packet is sent from the host interface, a hardware interrupt is generated. The hardware interrupt is processed by the device driver and the value associated is placed in the mailbox software queue.


The idea is that the mailbox value sent from the software contains the amount of data to be offloaded by the host! The interrupt code is in the device driver, very far from the user space!


This is not available on our Ethernet firmware, FYI and the software layer SIPIF does not propagate _4FM_ReadMailbox().


Best Regards,
Arnaud





KevinNIST June 11, 2014, 10:23 AM (#2)

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Thanks. I'd like to do the same thing with an ML605 and a FMC125. Is the same triggering scheme possible? Is the BSP and function call the same?
-Kevin
 

arnaudNL June 11, 2014, 10:50 AM (#3)

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Dear Kevin,


No, our Ethernet designs are using ETHAPI which has no interrupt. Maybe a solution would be to use the ML605 on PCIe bus but feasibility should be studied, contact sales@4dsp.com to discuss that further. I know we have both PCI and DDR3 stars for ML605 but they don't come part of the standard BSP; the PCI core is the fruit of 10 years of development. The advantage of the PCIe?, well you will be able to stream 1.3GB/s over the bus..


The ETHAPI layer is nothing like a robust interface, no interrupts, no recovery, fire and forget style. It is really only designed to offload a few kilo samples here and there and not for any streaming; it does manipulate EthernetII packets, no stack, no IP, slowly manipulating EthernetII packets, the efficiency directly depend on the CPU speed and how busy the computer is..


Best Regards,
Arnaud

KevinNIST June 11, 2014, 12:26 PM (#4)

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The ML605 is bulky, and the card and extension just wont fit a PC's PCIe card slot. Is it possible to use a PCIe extension cable like this one? Would the design still work?
http://www.digikey.com/product-search/en?pv77=936&FV=fff40018%2Cfff802e7%2C700966%2C74001e%2C1668000e&k=PCIe&mnonly=0&newproducts=0&ColumnSort=0&page=1&quantity=0&ptm=0&fid=0&pageSize=25
 
-Kevin

arnaudNL June 13, 2014, 08:16 AM (#5)

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Dear Kevin,

Not sure if such a cable will work, we are not using those. A solution would be a PC720 from us, it is quite cheap!

Then you would get FMC104 on PCIe and a 7 serie device instead your Virtex 6!

Thanks,
Arnaud

arnaudNL June 16, 2014, 04:34 AM (#6)

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Dear Kevin,


Is there anything else I can do before to close this topic?


Best Regards,
Arnaud

KevinNIST June 17, 2014, 04:25 PM (#7)

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One more thing... We did go ahead and order the FMC125. You mentioned that the ML605 did not have PCIe as part of the Standard BSP. Do you have a PCIe BSP that I can try out with the ML605 and FMC125?
-Kevin

arnaudNL June 18, 2014, 10:08 AM (#8)

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Dear Kevin,


The PCIe firmware has a cost because it comes with some support. Typically there are many issues on ML605 and it will be tough to get it up and running.


You should surely consider a card as the PC720, it is so less bulky!


Thanks,
Arnaud

arnaudNL June 18, 2014, 10:08 AM (#9)

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This topic is being closed because the issue is considered as resolved by 4DSP. Feel free to create a new topic for any further inquiries.