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  1. 3 points
    An FPGA can be a useful "swiss army knife", but all the nice features aren't easily accessible. Enter "LabToy": A batteries-included collection of utilities, just double-click and go. As the name implies, this isn't meant to compete against "real" test equipment. The main selling point is like a pocket knife - this fits into a shirt pocket and the power tools don't. And speaking of "selling points", it's free to use. So what do we have here: - Digital data: Shows the input state of all pins - Analog data: Readings from the two ADCs, up to about 700 ksps sustained (XADC "simultaneous sampling" mode, phase-accurate between channels) - Streaming data logger: Both analog and digital data can be written to a .vcd file, to be shown in gtkwave. There is no limit to the capture length. - Analog signal generator: 8 fully independent channels, sine, square wave, the usual suspects. Well, the DACs won't win any audiophile awards, but they are usable. - "Programmable" digital LED mode: Configurable pulse width to suppress short glitches, or edge detect with a built-in pulse generator to highlight them. - Analog LED mode: Shows the input value of the ADC in real time Some screenshots: 1k sine / cosine from DAC jumpered to ADC (in gtkwave) The digital signal is the generator's sync output that can be recorded as a digital input. Realtime display of the inputs. With pocket knives in mind ("this button will unlock the large blade, allowing it to be manually returned to its folded position") I decided to keep the screen uncluttered and put descriptions into tooltips. The large displays are the average voltage readings from the ADC. The smaller ones show the digital inputs in groups of four. Generator controls (frequency, minimum voltage, maximum voltage, phase). The voltage scaling is a bit unusual (typically there is "AC magnitude" and "DC offset") but I chose this approach because it shows clearly the limitations of the 0..3.3V output range. Most people will probably leave all this at the default values for a full-scale signal. Data capture Example: The output in gtkwave after I touched a jumper cable to the digital inputs on the DIL connector. +++ DO NOT USE THE +5V OUTPUT P24 FOR THIS KIND OF TEST +++ (3.3 V is available on the PMOD connector, bottom row) The red "undefined" marks flag the first input in an 8-bit group. In this example, they aren't too meaningful, but they can alert me to the fact that no data events have been observed yet. LED control The two numbers give the number of consecutive 1 or 0 samples (at 125 MHz) before a signal change is propagated to the LED. E.g. put 125 million there and it'll take one second after changing the input state for the LED to light / go dark. Those can be used interactively to study an unknown signal. "Level": no further processing ("level" mode and 1 / 1 sample counts is equivalent to directly connecting the LED to the physical input) "Edge" mode generates a brief pulse on signal changes, the LED is dark otherwise. "Invert" flips the input right next to the pin (0 becomes 1, black becomes white and man gets himself killed on the next zebra crossing -DA). How to get it: The file is attached: labToy0v1_beta.exe The installer unpacks a single .exe. Happy hacking! Requirements: Windows 64 bit (!) .NET 4.5 FTDI libraries CMOD A7 35 T (not 15 T). Warnings: Direct access to digital IO pins is an inherently dangerous activity. "PROVIDED WITHOUT WARRANTY OF ANY KIND" means Just That. And beware of the +5V pin. PS: If you try it, kindly let me know whether it works, or what goes wrong.
  2. 3 points
    A few reasons are... a - The introduction of logic hazards can cause glitches : https://en.wikipedia.org/wiki/Hazard_(logic) b - Routing of clocks is very complex - It is hard to ensure that the same clock edge appears all over the FPGA at almost exactly the same time. Sometimes this is achieved with 'slight of hand' (e.g. using a on-chip PLL to advance phase of the clock, so that by the time it reaches the edge of the chip is in back phase with the original signal). Low-skew paths also exist, but are restricted to small areas of the FPGA, and the clock has to be connected to the correct pin to be placed and routed correctly. c - FPGAs and their tools are designed to behave predictably under the "synchronous digital design" paradigm (something like https://hps.hs-regensburg.de/scm39115/homepage/education/courses/red/2_SynchronousDigitalCircuitDesignRules.pdf). If you work outside the paradigm you will be fighting against the tools and their assumptions. d - There is almost nothing that you are unable to code in an FPGA friendly way, but there are infinitely many ways to write FPGA-hostile code. If you want your FPGA to place nice with you, you have to play nice with it. So you can either add an RC filter to debounce you switch, or you can sample it using a reliable clock.
  3. 3 points
    D@n

    Just for fun: Frequency Resolution challenge

    Hello everybody! Since I was sharing this image with others, I thought I'd share it here at Digilent as well. The attached image shows the frequency response of several FFT windows, including the well-known rectangle and Hanning windows. The blue window is one I've put together, but haven't shared the FPGA source code used to implement it. I challenge anyone to do better. Oh, and one other comment ... all but the Hanning window can be used in an invertible FFT process. Dan
  4. 2 points
    Hello @bitslip, Things are a little bit more complicated. Indeed, for changing the resolution you have to rewrite some registers. But you also need to make sure that the Video Trimming controller ip generates the required constants for you resolution. I wouldn't recommend to write all the needed registers from the control interface (it would be agonising) Instead I would go with the existent logic for changing the resolution, which is adding a new structure with all the register values. As an example, you can check the OV5640.H file. I much simple and quicker solution would be to use our video scaller ip. This ip was written in HLS and it was used in the fmc pcam adapter demo for re-scalling the video at a 640x480 resolution. You can check the design in here: https://reference.digilentinc.com/learn/programmable-logic/tutorials/zedboard-fmc-pcam-adapter-demo/start Best Regards, Bogdan Vanca
  5. 2 points
    Hi @Blake, I was struggling with the same problem. In Adam's project is mistake which result is an FMC-HDMI module is not recognizable by other devices. The reason for that is not sending EDID at all. The cause of this situation is wrong initialized EDID map. In Adams example EDID is initialized by: but the correct way is: the body of iic_write2 is from LK example: By the way, in LucasKandle example initialization is done in same way as in Adam's example so is the reason why it not worked in your case. I hope it will helps. If you want I will post my working code for a ZedBoard with FMC-HDMI when I clean it because at the moment is kind of messy.
  6. 2 points
    kwilber

    Pmod DA3 clocking

    It seems to me the AXI Quad SPI block is sending address + data. Looking at the .xci file again, I see C_SPI_MEM_ADDR_BITS set to 24 bits. So 24 bits of address and 16 bits of data would yield 40 bits.
  7. 2 points
    The warning you pasted is benign and simply means there are no ILAs present in your design. The real issue could be your clock. You should review the datasheet for the dvi2rgb.Table 1 in section 5 specifies RefClk is supposed to be 200Mhz. Also, your constraint should follow the recommendation in section 6.1 for a 720p design. Finally, @elodg gives some great troubleshooting information in this thread.
  8. 2 points
    Hi @akhilahmed, In the mentioned video tutorial, the leds are controlled using "xgpio.h" library but the application is standalone. If you want to use a linux based application you have to use linux drivers for controlling. In the current Petalinux build, which is used in SDSoC platform, UIO driver is the best approach. Steps: 1. Vivado project generation: - Extract .dsa archive from /path_to_sdsoc_platform/zybo_z7_20/hw/zybo_z7_20.dsa - Launch Vivado - In Tcl Console: cd /path_to_extracted_dsa/prj - In Tcl Console: source rebuild.tcl - In this point you should have the vivado project which is the hardware component of SDSoC platform. Open Block Design. Change to Address Editor Tab. Here you will find the address for axi_gpio_led IP: 0x4122_0000 2. Petalinux UIO driver: - Launch SDx - Import zybo-z7-20 SDSoC platform - Create a new SDx linux based project using a sample application (e.g. array_zero_copy) - Build the project - Copy the files from /Dubug/sd_card to SD card - Plug the SD card in Zybo Z7. Make sure that the JP5 is set in SD position. Turn on the baord - Use your favorite serial terminal to interact with the board (115200, 8 data bits, 2 stop bits, none parity) - cd to /sys/class/uio - if you run ls you will get something like: uio0 uio1 uio2 uio3 uio4 uio5 - Now you have to iterate through all these directories and to search for the above mentioned axi_gpio_led address: 0x4122_0000 - For example: cat uio0/maps/map0/addr will output: 0x41220000, which means that the axi_gpio_led can be accessed using linux uio driver through uio0 device. - Code: #include <stdio.h> #include <stdlib.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <stdint.h> #include <unistd.h> #include <fcntl.h> #define UIO_MEM_SIZE 65536 #define UIO_LED_PATH "/dev/uio0" void UioWrite32(uint8_t *uioMem, unsigned int offset, uint32_t data) { *((uint32_t*) (uioMem+offset)) = data; } uint32_t UioRead32(uint8_t *uioMem, unsigned int offset) { return *((uint32_t*) (uioMem+offset)); } void led_count_down(uint8_t *ledMem) { uint8_t count = 0xF; uint8_t index = 0; for (index = 0; index < 5; index++) { UioWrite32(ledMem, 0, count); count = count >> 1; sleep(1); } } int main() { // Set Leds as output int led_fd = open(UIO_LED_PATH, O_RDWR); uint8_t *ledMem = (uint8_t *) mmap( 0, UIO_MEM_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, led_fd, (off_t)0); UioWrite32(ledMem, 4, 0x0); // Set all leds as output while(1) { // Start led count-down led_count_down(ledMem); } return 0; } - Build the project and copy the content of Debug/sd_card on SD sd_card - Power on the board and connect to it using a serial terminal - run the following commands: mount mmcblk0p1 /mnt cd /mnt ./project_name.elf - Result: A countdown should be displayed on leds.
  9. 2 points
    JColvin

    Arty A7 flash chip

    Hi @D@n, I believe the new part that is used in the Arty A7 boards (and other A7 boards) is now a Spansion S25FL128SAGMF100; based on old schematics, I believe this was added in Rev D of the Arty A7 (dated August 2017), though I do not know when that particular Rev was then released (or if it even was released) to the public. I confirmed that the Arty S7 also uses this part and I wouldn't be surprised if most of our other Artix 7 based boards use it now as well. I've requested that the chip name and images are updated in any appropriate tutorials and requested that the pdf version of the reference manual (updated wiki) is updated as well. Thanks, JColvin
  10. 2 points
    attila

    Math on FFT traces

    Hi @lab!fyi In the Network Analyzer extended option lets you use Wavegen channels at up to 20MHz and with external up to 50MHz. In the Spectrum Analyzer you can select frequency range up to 10MHz but with auto option lets you set Stop frequency up to 50MHz. Selecting the dB unit will let you specify custom reference, for dBm I think it should be 0.316V
  11. 2 points
    @hamster I was able to run your AXI Slave interface. It works great! It is now very easy to exchange information between PS and PL, and it even supports execute-in-place (e.g. I can put ARM instructions to register file and run PS CPU directly from it). I have some questions about your AXI Slave design: 1) AXI_a*size has no effect on INCR type of burst transactions, but according to AXI protocol: the increment value depends on the size of the transfer. You set it only for WRAP type, is it correct? Thus, burst size is always 0 for INCR type? 2) Do you know how PS initiates INCR burst type? A kind of memset/memcpy need to be used for that or an incrementing pointer will also work? 3) Where WRAP type is necessary? How to use PS to work in WRAP mode? You may also update your wiki page with following: 0) Create provided VHDL files 1) Create a block-diagram and add PS IP core to it 2) Apply configuration provided by your board's pre-settings; this will set all necessary initialization settings for PS (e.g. clock frequencies, DDR bindings, etc.) 3) Press auto-configure (or how it's called) ==> this will connect PS IP to DDR and to fixed IO 4) Add "External ports" to the diagram (create new AXI_CLK and AXI external ports) and connect them to PS ports 5) Generate VHDL wrapping code for this block diagram 6) Put generated system under axi_test_top by renaming it to axi_test_wrapper (default name is design_#_wrapper in my Vivado version) 7) This will auto-connect block-diagram external ports with axi_test_top 8 ) Add constrains file and rename/uncomment external ports where necessary 9) Generate bitstream 10) File->Export->Hardware and create .hwf file which contains PS configuration 11) Open Xilinx SDK and create a new project: select .hwf file as Hardware BSP for this project 12) Now, Xilinx SDK will auto-generate few .c and .h files which contain necessary PS initialization ==> clocks, IRQs, DDR, etc. 13) Add hello_world.c application to the project @hamster Thank you very much. I've learned a bunch of new things thanks to your help!
  12. 2 points
    mohammadhgh

    Zybo z7-20 Zynq Presets

    Hi @Mahesh, As @jpeyron said in the post marked as accepted solution, the Zynq processing system will be configured with the board presets when you first add the Zynq processing system IP core to the block design and run the block automation task from the green message that appears! Just remember to keep the Apply Board Preset option checked as shown in he picture. So this means if you are using the pre-built block design from the example project, a possible solution can be to remove the existing Zynq processing system block and adding a new one!
  13. 2 points
    xc6lx45

    Cmod A7 oscillator question

    PS: Reading the above post: I suggest you DO use the IP wizard, not calculate it manually. Pain does not equal gain.
  14. 2 points
    xc6lx45

    Vivado slowness reality check

    For comparison: My labToy project on CMOD A7 35 builds in 3:40 min (excluding clock IP, measured on my wristwatch by resetting synthesis, then "generate bitstream"). It's not a large project - about 20 % of DSP used and slices touched - but not trivial either. A hello-world project compiles in maybe 1 min, give or take some. But my desktop was built for the job (water-cooled i7 4930 @ 4.5G, 32G quad-channel RAM, M2 SSD). Most of this doesn't help with a one-LED design, but there are a number of things that will slow down the run considerably: - Use correct timing constraints: For example, a LED driven from logic clocked at 200 MHz can be very difficult to route (but at the 12 MHz crystal frequency it shouldn't matter much). A simple set_false_path -to [get_ports LED] makes it "don't-care". - Throw in extra registers where appropriate, especially between blocks (which tend to be physically separate). Most of the time, it does not matter whether the signal arrives one or two clock cycles late, and some spare registers will simplify implementation. This is especially useful for register rebalancing. - For the extra registers, it may make sense to use a "don't touch" attribute. E.g. in Verilog: (* DONT_TOUCH = "TRUE" *)reg [5:0] wa [1:NWRDELAY]; (* DONT_TOUCH = "TRUE" *)reg [17:0] wd [1:NWRDELAY]; (* DONT_TOUCH = "TRUE" *)reg we [1:NWRDELAY]; When I have multiple, parallel instances of a timing-critical block, the input registers are logically equivalent, get optimized away, and then P&R takes ages because timing is so difficult. The "don't touch" attribute" keeps them separate, possibly using a couple of FFs more than strictly necessary. - Removal of redundant logic can take a long time. For example, when I simulate pipelined DSP like the "labToy" generators I simply carry all data all the way through the pipeline, even though most of it isn't needed. Optimization will eventually remove it, but the cost is runtime. The LabToy example includes 8 instances each with a 6-lane 14-cycle 18-bit wide pipeline, and it adds minutes to the synthesis time if I don't remove the unused ends of delay chains in the source code. - Read and understand every warning, and read the timing report. "The compiler is my friend" For example, with PLL blocks it is easy to create duplicate clocks with the same frequency (one from the constraints file, one from the IP block). Timing analysis tries to (and will eventually) sort out all possible interactions, but it takes a lot of time and can create meaningless but difficult routing constraints. - Fix "critical warnings" related to timing. Even if common sense tells the design will work e.g. classroom demo with buttons, Vivado will waste a lot of time trying the impossible.
  15. 2 points
    I solved my ethernet problem and the specific connections to make it work. I didn't have I2C enabled on the Zynq7 customisation. so I also enabled I2C over EMIO. I think this hampered it's ability to communicate with the address chip I changed in the Zynq 7 processor MIO configuration - the ENET0 MDIO device is now MDIO pins MIO 52-53.
  16. 2 points
    @Shuvo Sarkar What exactly needs to be done depends on what you mean by "region of interest" and "binary mask". I will assume that you are trying to replace some area of what is being displayed on the screen with a rectangular image. A good starting point would be to take the input stream and output it with modifications. The DemoScaleFrame function in video_demo.c does this. The resolution scaling being done by this function also may or may not be desirable for your project. The Bilinear interpolation function implemented on line 473 of the original source is the primary point of interest here. The three variables required to tell what is being written to in the destination frame are the index, i, which can be used to determine the color channel being written to, and the destination coordinate variables xcoDest and ycoDest. A good starting point to be able to see changes being made would be to add extra code to black out a rectangular area of the screen. This can be accomplished by wrapping the destFrame[iDest] statement within an if statement, that either writes a zero to destFrame[iDest] or runs the bilinear interpolation of the source frame, depending on the coordinates of the target pixel in the destination frame. How you store, access, and process the binary mask (overlay image?) is a large topic that I would need more details to provide information on. Let us know if you have more questions. -Arthur
  17. 2 points
    attila

    Analog Discovery 2 vs Raspberry Pi 3

    FTDI USBs like AD, AD2, DD are not working with RPI model B (1,2,3) data packets/bytes are randomly lost. The EExplorer with different USB controller is working fine on these. All devices are working with other embeddeds: Zed, Zybo, BeagleBone… According reports AD is working with the original RPI model A and probably Zero because it has similar chipset/USB. The problem seems to be with FTDI or RPI B USB, library or hardware. You can find such comments regarding RPI problems with other devices too. Unfortunately we couldn't remediate this problem.
  18. 2 points
    @Sam_a Should be fixed this time. Thanks for your patience, Arthur
  19. 2 points
    Notarobot

    Zynq PL-PS Interrupt issue

    @artvvb The issue seems to solved after I've added the statement: XScuGic_SetPriorityTriggerType(IntcInstancePtr, INTC_INTERRUPT_ID,0x00, 0x3); Now the applications responds and counts interrupt sisgnals coming fro PL. Regards, N
  20. 2 points
    @dcc, If you actually want to set/read memory, you'll need to learn how to interact with a bus. I like to use a B4 pipelined wishbone bus. I find it very simple and easy to use. For example, you can find a very simple block RAM device here that interacts with a wishbone bus. (It would be even simpler if I wasn't keeping my high speed and low speed code in the same file ...) Xilinx has committed themselves to the AXI bus--a bus that requires the management of five separate data paths just to get right. If you want access to DDR3 SDRAM, you'll need to use Xilinx's memory interface generator (MIG) to build an interface for you. (I tried without MIG, made lots of progress, but ... after two months of full time work on it hadn't finished the task. It's a shame. The memory access delay would've been about half of what Xilinx's delay is.) Xilinx's MIG generates a DDR3 interface to a memory using an AXI controller. You can see how I interact with that AXI controller in my own Arty design here. Within that file, take a look at the mig_axis component and then roll your eyes with me at the quantity of wires and communications paths you need to handle just to read or write from memory. Yuck. That's why, in the same file, you'll find a wishbone to axi bridge, one I call wbm2axisp, or wishbone master to AXI slave pipelined. As a result, I can interact with that core using wishbone signals, such as i_wb_cyc to indicate that I am accessing the bus (needs to be high throughout the transaction), i_wb_stb to request a memory interaction (only needs to be high for one clock while o_wb_stall is low per request), i_wb_addr (specifying the address of my request, must be valid any time i_wb_stb is high), i_wb_we (specifies if I am reading or writing), i_wb_data (data to write, must be valid anytime i_wb_stb and i_wb_we are high), o_wb_ack (true any time a memory access completes), o_wb_stall (true if the memory isn't ready to accept a transaction), and o_wb_data (the data result of any read transaction). The number of wishbone signals are truly ... much less than that giant AXI bus. (10 signals, of which 4 have multiple bits associated with them.) Looking at the AXI bus, to interact with it you will need 35 signals, of which 23 have multiple bits. Take your pick. (By the way, going from an 8-bit data width to the 128 bit data width used by the DDR3 SDRAM is not nearly as hard as it sounds, if that's something you would be struggling with.) If you are trying to read/write from memory to support both an ADC and a DAC, you'll need a couple of things. One of them is a FIFO. You can see an example of a FIFO supporting a UART here. DDR3 memory speed can be unpredictable, and it can drop out suddenly for a refresh cycle while you are trying to interact with it. Worse, that MIG interface takes upwards of 24 clocks to complete a transaction. (If you pipeline your requests, only the first will take 24 clocks, the rest can take one clock. See the wishbone B4 spec for a discussion of this.) However, with a FIFO you can weather some of these problems without dropping samples, and even get on and off the memory bus faster. Second, you'll need an arbiter--something that decides of the two transactions you'd like to make, which of them actually gets access to the bus. You can find my own wishbone arbiter here. If you are wondering just how to get a wishbone transaction working, I have examples ranging from simple to complex. For example, here is a simple prefetch example that just reads a single value from memory (i.e., the next instruction for a CPU). Here's another, similar example, which reads two values from memory at a time. (When working with that SDRAM, the first can take 24 cycles per read, the second can do two reads in 25 clock cycles.) And, while we are at it, here's an example which reads 2^N values at once--but since it's got a cache within it, it ... tends to be more complicated. Another example would be the code I've used for building my own DMA. Take your pick. How deep would you like to dive into this? I could go on and on for a while with more examples ... Is this the sort of thing you are looking for? Let me know, and I can offer more, explain any of the above, or ... you tell me. Yours, Dan
  21. 2 points
    The trick is your code does not need to infer a block memory generator. It will actually need to explicitly implement the block memory generator INTERFACE. This is because the block memory generator is already being instantiated in the block diagram. You will need to design a state machine in VHDL that properly implements the interface. For a description of the signals (en, we, addr, etc.) you should refer to the block memory generator Product Guide. You can find the guide by double clicking the block memory generator IP and selecting Documentation in the upper left corner. The end goal will be to create a custom IP core that contains this custom VHDL. Since you do not have an AXI interface on your core, this should be pretty easy. I believe you can just create a new project that targets the ZYBO and has its top level ports be the desired ports on the IP block. Then I think you can run the Create and Package IP wizard from the tools menu to convert the project to an IP core so it can be inserted into you block diagram (which will be in a different vivado project). I'd recommend simulating your project before you convert it to an IP core to help make sure it is functioning as expected. BTW, you can just expand the BRAM_PORTB interface on the block memory generator IP core and manually connect each of the signals to your IP core if you have difficulty making you custom IP implement the BRAM interface. See the picture below for an example of what your end goal will be:
  22. 2 points
    @silverwolfman, I don't have my S6 on my desk to tell you how much time it took me to load the flash, but I do know I didn't use iMPACT. You can find my work here. In particular, the flash loader is called zipload, and depends upon the using the Digilent Adept utilities to load an initial configuration (generated from this toplevel file) into the flash. Dan P.S. I'll be redoing my work again soon, to prove that the updated ZipCPU can still fit (and work) on the device. You can see some of my update works in the 8-bit branch of the s6soc project, but ... although it builds, it hasn't been tested yet so ... it's still a work in progress.
  23. 2 points
    @Hassan Iqbal, Can I try to answer? Your solution will have two parts. The first part will feed the camera image constantly into memory. When you get the vertical sync to start again at the top of the page, you just reset your write memory pointer. The second part of your solution will read the image out of memory on your other clock. This will read out with the synchronization parameters you are trying to achieve. This way, if you write faster than you read, you'll quietly and slowly drop a frame, and if you read faster than you write, you'll eventually get a full frame stuffed into your stream--but either way things will work. This approach will use a "nearest-neighbor" interpolator, and will handle over and underruns by frame dropping or stuffing respectively. The trick you will have is that you only have one interface to memory. For that reason, both video streams will need to buffer their work into a FIFO. When the writer's FIFO is roughly half full, then it will need to write to memory until it's FIFO is empty. Likewise, when the reader's FIFO is half full, it'll want to initiate a read until its FIFO is full. This way, if both the writer and the reader want to access memory at the same time, they'll both be able to wait until the other completes it's memory access request/requirement. I haven't checked on your memory timing requirements at all. That could make things difficult. If it makes things impossible, then drop color bits and you should be able to get back into the realm of possible again. As for how to handle the multiple clocks, you will have three clocks you will need to deal with and work from. Two of these are your pixel clocks. The third is your memory clock. You can synchronize from the pixel to the memory clock and back again using the single "FIFO is half-full" wire. Dan
  24. 2 points
    WereCatf

    Stretch Goals?

    I ain't got anything specific in mind. For now, I'm just throwing spaghetti at the fridge and seeing if any of it sticks!
  25. 2 points
    D@n

    XADC demo

    @Manas, Sam is trying to turn voltage = (12-bit-code)/4096 into microvolts = (1000)*(1000)*(12-bit-code)/4096, and he's trying to avoid division. Rearranging: 1000*1000/4096 = 500*500/1024 (just by dropping common factors of two from both numerator and denominator) Shifting right by ten is equivalent to dividing by 1024, and then he multiplies by 500*500. Looks like it works alright. I might be concerned personally about losing any precision in the divide by 1024 (i.e. shift right by 10), especially since it is being done before the multiply if I understand correctly--leaving you with only 2-bits of precision (did I read that right?). Looking at the above, you might simplify it further into a shift right by 6, followed by a multiply of 15625. To get here, all I did was cancel out any factors of two that were in both the numerator and denominator. Then --- rearrange your order of operations, so the multiply is done first. What makes this choice special is that 15625 can fit within an 18-bit multiplier. Hence you can do: A = 15625*(12-bit-voltage-code) inside a DSP multiplier, and hence inside one clock. The result of this multiply will be a 30-bit number. If you ignore the bottom six bits, the 24-bit number that remains will be the number of microvolts that you are looking for. Converting this to a decimal display might take some more work though. Dan
  26. 1 point
    I will try it to see how it works. Thank you too.
  27. 1 point
    To clarify, the Microblaze clock was set to 100Mhz, and the Axi Quad SPI used the default internal frequency ratio, which I think is 16, so I got a SCLK frequency of around 6 Mhz. But you say that you fixed it, and I want to know which mode did you use and it's working properly with Pmod DA4?
  28. 1 point
    I receive and process serial data in this hack: http://hamsterworks.co.nz/mediawiki/index.php/PmodMAXSONAR It looks for an R character, then takes numeric ('0' to '9' ) that appear after that.
  29. 1 point
    Hi @Lesiastas As initialization when you application starts, before calling open set the following option to 0/Run: dwf.FDwfParamSet(DwfParamOnClose, c_int(0)) # 0 = run, 1 = stop, 2 = shutdown 2 - open always takes 'long' time (~300ms) since the device is powered down on close and reprogrammed on each opening 1 - device remains powered but the outputs are stopped on close, this takes a few ms on open/close * 0 - device continues the output after close (waveform, pattern generation, supplies), the open/close are fast * *The first open after power up will take 'long' time since the device needs to be programmed.
  30. 1 point
    jpeyron

    Nexys 2 - transistor part number

    Hi @CVu, Glad to hear that replacing the transistor fix the issue. Thank you for sharing what you did. best regards, Jon
  31. 1 point
    Hi @kmesne, We responded to your other question here with some detail, but I will try to elaborate a little bit more here. The Pmod COLOR is not intended to detect colors from any sort of distance, so you would need it next to the red/green light indicator and then have it transmit data to the main controller for the car as opposed to be mounted on the car (unless the red/green indicator was on the car itself). I believe the Pmod COLOR could detect the green in a green cube, but it would need to be fairly well lit up due to the limitations of the sensor itself. As a bit of perspective, this will be a large and non-trivial state machine (especially for first semester project) with a lot of conditions to be covered; is light red or green to control the enable bit on 2+ H-bridge drivers running the motor, which needs to be checked frequently in order to obey traffic laws, as well as the enable bit being toggled as appropriate when changing input directions if the vehicle can go in reverse to avoid burning out the h-bridges, pwm control over the enable pin to allow the vehicle to turn; all done over (presumably) 3 remote systems communicating with each other; the controller with the direction buttons, the color sensor detecting the light change, and the RC vehicle itself. Which system/input will have priority in the state machine and how often will you need to check each input to provide a "smooth driving experience" will all be things that you need to consider. Some good resources for VHDL basics can be found at asic-world.com and fpga4fun.com, as well as this page that discusses state machine construction in VHDL. Thanks, JColvin
  32. 1 point
    Well that's a pretty horrible looking 5 MHz signal coming directly out of an MMCM. It does remind me of the characteristic response of a particular passive component to a pulse, from decades ago when I took my intro electronics course. What do you think? Remind you of anything? I didn't mention the idea of scope probe compensation. It sure doesn't look like something that even a cheapo compensated probe would present for a low frequency signal out of a functioning FPGA pin into a high impedance load. Past that there are a number of usual suspects... but something is fundamentally wrong with your test setup.
  33. 1 point
    Nianyu Jiang

    PmodIA Extension

    https://www.researchgate.net/publication/236037769_A_four-electrode_low_frequency_impedance_spectroscopy_measurement_system_using_the_AD5933_measurement_chipt this is the paper I am talking about. Thanks for the further explaination, I start understanding the working principle and trying to combine everything. Will go back to you once I have more question. Nianyu Jiang
  34. 1 point
    Hi @Amin, I know our content team is planning on updating our Petalinux projects. We currently do not have an ETA for this. Here is the Petalinux Support for Digilent Boards table that shows what Petalinux projects we have for our development boards and has a link to them as well. To use our most recent Petalinux release for the Zybo-Z7-20 I would suggest to download Vivado/SDK and Petalinux 2017.4. I would also suggest reading the Petalinux projects detailed readme as well. thank you, Jon
  35. 1 point
    jpeyron

    Zedboard DMA Audio Demo problem

    Hi @Brinda, You want to download the release version of Zedboard DMA project here. I was able to generate a bitstream without issues in vivado 2016.4. Unfortunately, Vivado projects are version specific. This project was made in and works with Vivado 2016.4 without having to make alterations to the project. What version of Vivado are you using? cheers, Jon
  36. 1 point
    Hi! Check page 45 in https://www.xilinx.com/support/documentation/boards_and_kits/zc706/ug954-zc706-eval-board-xc7z045-ap-soc.pdf It stated: N8 MGTREFCLK0P_112 PCIE_CLK_QO_P A13 (1) N7 MGTREFCLK0N_112 PCIE_CLK_QO_N A14 (1) So just create clock input pins in your block diagram with any names. After that define constraints in xdc file which connects your clk names to N7/N8 pins.
  37. 1 point
    Hi @jma_1 See the help of the application: The Protocol interface uses the device Digital Pattern Generator and Logic Analyzer resources to transfer data using UART, SPI, and I2C protocols. When the Debug option is enabled, the Logic Analyzer can be used to investigate the signals. In this case, the Protocol instrument will not receive data, it will only send data.
  38. 1 point
    jpeyron

    Compatibility Pmod Boards <-> Pmod Ports

    Hi @sourav, Here is a forum that has information on using the xadc on the zedboard. Here is Zedboard.org projects. Here is a non digilent tutorial on using the xadc with the zynq. Here is the zedboard reference center that has the FPGA Package Pins to FMC information. I would also look in the zynq book here. thank you, Jon
  39. 1 point
    Hi @BYTEMAN, I am not aware of a way to have those specific microblaze configuration pages to be used after the initial block automation. I would suggest to reach out to xilinx about this question. I believe you are correct about the xdc overriding the board file defaults. thank you, Jon
  40. 1 point
    Hi @BYTEMAN, Reading through your post i do not see an issue with your process for making external pins and constraining them with the xdc. In regards to the reset pin I reached out to one of our design engineers about this and they responded that the oscillator on the CmodA7 always runs so there is no way to stop or reset the input clock. If you want to reset the clock in a MicroBlaze design then you need to connect the reset pin of the MMCM block to an external pin, such as BTN0 or BTN1. They typically tie the clock reset pin of the MMCM block to a constant in my MicroBlaze block designs. It’s either a constant ‘1’ or a constant ‘0’, depending on what the active state of the Reset is configured for. You can see how we configured the microblaze for the cmod a7 35t by looking through the board files here. After you do block automation you can customize microblaze to your needs. The preset for microblaze that the board files facilitates configures microblaze for the cmod a7 so altering the setting can make issues with your design. thank you, Jon
  41. 1 point
    attila

    I2C ACK before STOP bit

    Hi @kdumont According the I2C specs the address and written bytes are acknowledged by slave. The read bytes are acknowledged by the master except the last byte before stop. A master-receiver is done reading data and indicates this to the slave through a NACK.
  42. 1 point
    zygot

    Capabilities of Zynq-7000 DevBoards

    So, for most Zynq boards the DDR Ram is attached to the ARM core(s) and is used by the OS or whatever minimalist software the cores run on. A few Zynq boards also have additional DDR RAM connected to the PL. If you are using one of these then you would have a nice buffer entirely reserved to store a large dataset. If you can reduce the data in real time the storage problem might go away. Now to the harder issue: Well, no. Now, if you have multiple ADC peripheral boards that you supply the clock and a CONVERT strobe that begins the conversion process on demand there might be some hope for "good enough more or less simultaneous" multi-channel ADC capture. Unfortunately specifying ADCs is not a trivial pursuit; there's a bit of an art to weeding through vendor datasheets to get vital information, and the vendors want to sell chips so they don't make it easy. Trust me, I speak from experience. Usually the multi-channel low conversation rate ADC are SAR types. A few of these have independent ADCs for each channel. Some have analog sample and hold circuitry to more or less allow "simultaneous" conversion of all of the channels. Others have programmable channel sequencer logic to schedule which channels get sampled and when. Finally, multi-channel ADC ICs have some level of inter-channel coupling of input signals. This can range from not too bad to very significant. It can get complicated and be very time consuming to choose your ADC design. On top of this you should be aware that most ADC applications require some sort of front-end conditioning. For best results you want the maximum signal voltage going into the ADC to be very close to the maximum input voltage specification of the ADC. This is to preserve the dynamic range of the ADC. That is, if your signal is never greater than half of the input range then you are losing 1 msb of digital dynamic range. Also, there are anti-aliasing filters ( some ADC device offer programmable digital input filtering ). None of this is meant to discourage you... just to provide food for thought. ( For real world commercial applications the analysis and number of specs to weed through gets a lot more complicated and includes choosing a ADC architecture appropriate to the task at hand. ) Perhaps the simultaneous sampling of 3 1KHz and 3 100 KHz signals isn't really a requirement. But perhaps you can now understand why instruments that do capture and record multiple analog channels can become expensive.
  43. 1 point
    xc6lx45

    FPGA audio - ADC and DAC

    If I take it to extremes, the answer is surprisingly complex (this is how it's done inside the clock management tiles or a cellphone, for example). For household use, take (e.g.) a 32 bit counter and add "delta" at a high frequency, e.g. 100 MHz. Don't check for overflow, it will wrap around cyclically (which is the "correct" way to behave in this application. E.g. 0xFFFFFFFF + 3 becomes 0x00000002) For example, at 100 MHz clock, a delta of 1 gives a cycle time of 42.9 seconds (2^32 / 100e6). A delta of 43 gives a cycle time of one second. A delta of 42950 gives a cycle time of exactly 1 ms => 1 kHz. Now we've got a 32 bit number. Take the highest bits (as many as the DAC needs), voilà, a sawtooth generator. Plug that into your wavetable (you'll have to recalculate for a 0..31 range if using five ramp bits). Simple lookup from a block RAM (aka "nearest-neighbor / zero-order interpolation") will give abysmal audio quality, or the wavetable grows so large that it doesn't fit into the FPGA. So I need higher-order interpolation or a different algorithm (e.g. CORDIC for sine), and things get messy. PS: When working with signed numbers, check Verilog's "signed" keyword. It's not mandatory, but makes life easier.
  44. 1 point
    jpeyron

    Vivado version for Arty Z7-20

    Hi @Mahesh, I was able to get the arty-Z7-20 hdmi out to generate a bitstream in vivado 2017.4. To do this you new a fresh project. Then upgrade the ip cores by clicking tools->repots->report ip status and upgrade/generate the ip cores. Then create a wrapper. The DVI2RGB ip core has been updated since this project was made. Because of the updated ip core you will need to change the xdc pin names in the xdc file. From hdmi_hpd_tri_i to HDMI_HPD_tri_i , from hdmi_ddc_scl_io HDMI_DDC_scl_io and from hdmi_ddc_sda_io to. HDMI_DDC_sda_io. Next generate bitstream. The rest should be the same steps to get project working. cheers, Jon
  45. 1 point
    Hi @JongSeob, HDMI_RX_PEEN is not routed. We didn't want the feature in our board and it was a mistake that the pin remained named. If you want to use it, you should check the specification AD8195. T3 is also not connected and for the PROG pins, they are part of the programming solution that we implement on our board and is a proprietary design. It should be where is the blank page in the schematic. That is the USB interface with the board. You should be able to find another programming solution for your board. You can ignore those pins Best regards, Bianca
  46. 1 point
    Hi @Jay Sngh, I have received the Declaration of Conformity's for the Basys 3, the Pmod USBUART, and the Pmod RS232. The other two Pmods (the Pmod LVLSHFT and the Pmod SSR) are exempted based on "subassembly exemption". All of our boards are designed with UL-94V0 rated PCB material and are RoHS Complaint. Let us know if you have any questions. Thank you, JColvin
  47. 1 point
    @electronicsdevices, Leaving the Vivado SDK? A good choice, IMHO. But ... how do you modify inputs and get outputs out? As you are discovering, it's not as easy as it sounds. Debugging can be a challenge as well. Your biggest problem: good engineering discipline and practice requires that no more than one component be under test at any given time. While I see you've minimized the items you wish to place under test, you've still got a lot of things to work with that .. each may fail individually. How you will isolate any broken component will be your challenge. This leads me to a couple of thoughts: Simulate your design first, before running on the hardware. I have found and love Verilator as a tool, and I've written a short tutorial on how to use it. Use a known working interface, one that isn't likely to suffer from electronic contact bounce (such as the switches), or need logic that needs to be debugged (the 7-segment display) to get yourself started. I recently described building such an interface on the ZipCPU blog. Indeed, I'm hoping to present measurements of button bounces later this week ... but that wasn't your question. I have used this basic approach with the Basys3 with complete success--it depends only on a working serial port, although I tend to use a more sophisticated debugging bus, that uses compression as well. Using such a bus, you might run a C++ program and give it a command such as fpga->writei(R_MATRIX_A, sizeof(amatrix), amatrix);, and then repeat for your matrix B. (The blog discusses how this interface works, and shows examples of how to build your own if you want.) The example code even comes with a scope that you can use to see what is going on within your design. You can find a discussion of how to set it up here. Much against my own better judgment, the example code is all nicely licensed under the LGPL. (I tend to use and like GPL) If you improve upon it, please share your improvements with others. What makes all of this really unique is that a lot of new FPGA designers, such as yourself, will try what seems like a very simple project (like the one you outline above), only to have something about it not work ... at which point these new FPGA designers get frustrated and often give up. I like to call this situation FPGA Hell, defined by when your logic isn't working and you have no idea why not, nor any trace giving you information about what went wrong. Hopefully this gets you moving in the right direction. If not, just holler, Dan
  48. 1 point
    jpeyron

    Analog Discovery Warranty?

    Hi @mrwesleycrusher. I am sorry that you are having issues with you Analog Discovery. Here is a link to our shipping and returns policies. What email did you send your issue to? I have sent you a pm about what email you used as well. So when you plug in the AD1 what does it show in Waveforms? The red light on the AD1 do not come on until its connected to waveforms. What OS are you using? if windows, what does the device manager show? cheers, Jon
  49. 1 point
    @Nilakshan The following XDC code may or may not work #Clock Signal set_property -dict {PACKAGE_PIN L16 IOSTANDARD LVCMOS33} [get_ports clk_50] create_clock -add -name sys_clk_pin -period 20.00 -waveform {0 10} [get_ports clk_50] You need to use the create_clock line to define the frequency of the clock, where the period and waveform parameters take values in nanoseconds. The more normal way to create a slower clock is to use Vivado's Clocking Wizard IP core to use the clocking hardware (MMCMs and PLLs) on the Zybo - I am unsure if Vivado interprets the period and waveform changes so as to use this hardware. Hope this helps, Arthur
  50. 1 point
    Hello, This board will connect to the nexys video. It was designed with the Zedboard in mind which uses the same FMC port as the video. For some more piece of mind you can look at the schematics and see that the FMC ports are of the same part and connection. (part ASP-134603) https://reference.digilentinc.com/_media/reference/programmable-logic/zedboard/zedboard_sch.pdf https://reference.digilentinc.com/_media/reference/programmable-logic/nexys-video/nexys_video_sch.pdf - Sam