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  1. Hello, can anyone tell me how I can check if any elemenent (e.g. switching matrix, etc.) of ArtixA7-35T is not broken? I have accidentally wrote to my Basys3 board bit file created for Arty... I have tested it with onboard demo (LED display, switches, LEDs and buttons) and everything look ok, but I have read that bit file programming internal switch transistors in switching matrix and there can be something damaged. Thanks in advance for any response Best regards Josef
  2. Hello @jpeyron Thanks a lot. I only found that DDR memory on revision D have resistors on data lines what missing on revision C, memory type is the same. Does it mean that DDR on Arty wouldn't work on same high speed as on Arty A7? Or I overlooked something in schematic? Best regards Josef
  3. Thanks for describe of troubles. So if I understand, problem is only when user access the flash from design (or own software in computer) and leave the memory in unknown type of communication SPI or QSPI/XIP and next time you want to download some data to this flash from computer, am I right? So driver from Digilent uses one type of communication (I guess, if you mentioned about high speed flash controller type SPI) and if I access the flash from design and leave the flash in QSPI/XIP, Vivado HW Server can next time have problem with download design to flash? Or standard download programs implements approach you also mentioned about switching memory from any type of communication to wanted type? So Micron memory I can left in board and use also for my configuration without any fear of incorrect boot? Best regards Josef
  4. So problem is in driver in PC, right? I looked once again and I think that newer board can also fit 100T version of Artix (some ceramic capacitors are also near of FPGA package diagonal on top side of board, what I doesn't have on my board). Can I ask for problem with flash, how you Dan found problem with memory power-on reset? What are symptoms and what steps I can also get into this trouble? Best regards Josef
  5. So if I understand Dan, Arty (revision C and earlier) have a flash config memory from Micron (IC3 or IC4 location) what have internal design problem caused by sometimes problematically power-on reset? So if I want Arty without problems, I have to exchange memory from Micron (N25Q128A13ESF40) to memory ideally from Spansion (I only found Cypress S25FL128SAGMFV003) on board, am I right? Best regards Josef
  6. Hello everyone, I searched for something information about programming interface for DDR3L on Arty board what I bought and I got on page - reference manual for Arty board and there is information saying that Arty reference manual is for revisions A - C of board. I have looked on my revision and on board is printed REV. C. Before I met this information I used schematics, reference designs and et cetera files from page Arty A7 and it seemes that all works fine. So I have two questions. If I downloaded materials for Arty A7, must I download materials for Arty, if I have revision C, or files for newer revisions is backward compatible with older revision of board? I think yes, because no warning information is on Arty A7 reference manual page. And I also have question what difference is between revision C and newer revision of Arty board? I haven't found any difference, but it's very likely that I have overlooked something. Thanks in advance for any response Best regards Josef
  7. @D@n Ah, in implementing memory controllers I don't have any experience, so it can be challenge implementing also SRAM controller and I think also DDR controller (I'm afraid of sensitivity both clock edges what I currently can't imagine how I will implement something like this). At SDRAM I only looked for access times. I have last question about generating VGA image. Can HyperRAM on two PMODs works on higher resolution? Space I think have enough (I think 8 MB), able working on 100 MHz, so resolution 1024x768 256 colors will be also possible also on Basys 2 with increase of pixel clock, am I right? Best regards Josef
  8. @D@n Thank you for your response. I like your 3rd idea, so the solution generaly can be using a DDR memory, is it right? And what SDRAM as I mentioned above, could be also useful? Best regards Josef
  9. Hello, thank you for your answer. I found also SDRAM IS42S16400J from Integrated Silicon Solution Incorporated. This memory has access times few nanoseconds (max 10ns). Do you think that this could be the way? Thank you in advance for your response Josef
  10. Hello everyone, I am a little newbie to generating VGA from any development kit, today I made a simple VGA image generation working on Basys 2 board with Spartan 3E-100. In code I'm currently using construction with IF sections for setting pixel colors at the required coordinates, but I think that this is not the best practise, because images is in this case programmed like in a ROM... So I would like to ask what is the best practise for storing images in Spartan 3E-100 next intended for displaying by VGA? I would prefer to have one component driving displaying to VGA from something like a buffer what can be modified outside of VGA component by pixels. My first idea was design own video RAM to FPGA in VHDL, but idea has failed after I waited for synthesis like a 20 minutes and nothing happened then I read some forum questions on RAM on FPGA and CPLD and I guess that 300 kB RAM (640x480 pixels represented by 1 byte per pixel) I am not able to achieve on Spartan 3E-100, am I correct? The next idea was use some external SRAM like AS6C4008 from Alliance Memory, but problem I think is on access time, because pixel clock 25 MHz is 40 ns and AS6C4008 access time is 55 ns, so I think that this is not a solution either. Last idea I have use on-chip RAM memory on FPGA, but currently I don't know whether is this idea correct and also how is correct way to use on-chip RAM on Spartan 3E and where I say to ISE that on-chip RAM I'm going to use in my design. Can anyone tell me whether my last idea can be realized or is also out of bounds and what is the best way to doing something like a video RAM or video array for VGA? Thank anyone in advance for reply. Best regards, Josef