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Showing content with the highest reputation since 05/23/18 in all areas

  1. 3 points

    Digital Twin

    Hi @Kris Persyn, It depends on how you manage your resources, driving immersive visuals on a HDMI display can be done in multiple ways at different resolutions, some are PL taxing others are DDR taxing; you could generate entire frame buffers in PL or PS or you could find a optimal algorithm to change just the previous frame or you could allocate a high number of frame buffers and then run them in a loop. It also depends on how math lab synthesizes the IP you will need to add to your design. If you design your project properly and don't aim for a resolution higher more 720p( I'm being conservative, we managed to drive the HDMI at 1080p with processing filters without a problem) I think it should be enough for what you want to do, resource wise. My suggestion, download and install Vivado, download and install the board files, create and implement your project look at the resource consumption and then buy a board. - Ciprian
  2. 3 points
    In your constraint file, the ddc pins have lowercase "ddc_scl_io" and "ddc_sda_io". Your block design has the port in uppercase "DDC". The case must match. Try editing your constraint file to have "DDC_scl_io" and "DDC_sda_io".
  3. 3 points

    pmod wifi

    Hi @harika, I believe the HTML web page error is related to the materials on the SD card. 1) Please attach a screen shot of the contents of the Sd card you are using. 2) Please follow the YouTube video here from about 6 minutes and 28 seconds on for how to set up the HTTP server project. Make sure to update the login an password for the router/modem you are using. thank you, Jon
  4. 3 points
    @thobie, the bare-metal purchase option for the Zybo was done to enable a lower price point for those who do not require the accessories. For the rest of our customers, adding the Accessory Kit is recommended during the purchase process. You are not the first and the last to complain about version compatibility. It is economically unfeasible for us to update all support projects, IP and support packages provided for free four times per year for each Vivado version. Instead we made a commitment to consider the last Vivado release in each year stable and do a once-a-year update cycle. In that regard, 2017.4 is the version we are upgrading projects to. There is a question whether OOB designs should be updated at all, or kept at the version which generated the binary image shipped with the board. The board presets are not versioned for Vivado (no version-specific releases in our git repo), because these should be forward-compatible with Vivado versions. The critical warning itself related to CK-to-DQS delays being negative appears starting with 2017.4. The negative values are due to CK trace being shorter than any of the four DQS traces. In the early days of Zynq board design negative values where listed as sub-optimal, but not erroneous. Tree topology instead of fly-by was also among the routing recommendations for DDR3 layouts. So the Zybo was designed with this sub-optimal layout due to space constraints. During Write Leveling calibration, 0 is used as an initial value instead of the negative preset delays. After calibration, if the skew is still too low, the clock is inverted. See ug585 pg 316 for more details. All Zybos shipped to customers are functionally tested and pass the DDR3 calibration process. Xilinx recommendations changed in the mean time, both in terms of routing topology and delay values. A trace of this can be found here: https://www.xilinx.com/support/answers/53039.html. The > 0ns requirement was introduced to be in line with non-Zynq MIG-based designs, where negative delays were never permitted. Since these delays are board-dependent, we would need to re-design the board to make the delay positive. This is impossible with the current form-factor. Another option would be modifying the board preset file and forcing a zero value instead of the actual delay. The tools seem to be using zero anyway for calibration. This will have to be thoroughly verified first.
  5. 3 points
    Hello, I've posted the next part in my FPGA graphics series using the Arty + VGA Pmod or Basys 3. It shows you how to make use of double buffering to animate sprites using simple Verilog. https://timetoexplore.net/blog/arty-fpga-vga-verilog-03 Feedback very welcome, Will PS. I'll add the source to GitHub shortly.
  6. 3 points

    WaveForms beta download

    3.11.7 digilent.waveforms_beta_v3.11.7_64bit.exe digilent.waveforms_beta_v3.11.7.dmg digilent.waveforms_beta_3.11.7_amd64.deb digilent.waveforms_beta_3.11.7.x86_64.rpm minor fixes and improvements 3.11.6 digilent.waveforms_beta_v3.11.6_64bit.exe digilent.waveforms_beta_v3.11.6.dmg digilent.waveforms_beta_3.11.6_amd64.deb digilent.waveforms_beta_3.11.6.x86_64.rpm Added: - Protocol - UART Spy - Max Lines option: log limit to prevent application slowdown - Line Wrap option - tooltips for UI controls listing Script access path - application and script Font options - dark theme support for Script 3.11.5 digilent.waveforms_beta_v3.11.5_64bit.exe Added: - Script open/save text file - application argument: -script myscript.txt/js Fixed: - warnings at low record rates 3.11.4 digilent.waveforms_beta_v3.11.4_64bit.exe Added: - Scope: - set/reset zero offset in each channel option - precision option for measurements Fixed: - Script: access to traces and channels from Instrument.Export - unit conversions V to Ṽ, A to à - I2S 32 bit data 3.11.3 digilent.waveforms_beta_v3.11.3_64bit.exe digilent.waveforms_beta_3.11.3_amd64.deb digilent.waveforms_beta_3.11.3.x86_64.rpm Fixes 3.11.2 digilent.waveforms_beta_v3.11.2_64bit.exe digilent.waveforms_beta_3.11.2_amd64.deb digilent.waveforms_beta_3.11.2.x86_64.rpm Added: - Spectrum, Network and Impedance Analyzer store time data when this view is open Fixed: - runscript argument - loading of docked views geometry 3.11.1 digilent.waveforms_beta_v3.11.1_64bit.exe digilent.waveforms_beta_3.11.1_amd64.deb digilent.waveforms_beta_3.11.1.x86_64.rpm Added: - Scope: out of range warning in measurements - Protocol/UART: - support up to 32bit/word - TX/RX format: text, binary, decimal, hex - Wheel Direction option - Logic Analyzer: option to swap previous/next events - Spectrum Analyzer: allowing higher number of BINs for CZT 3.10.7 digilent.waveforms_beta_v3.10.7_64bit.exe Added: - Spectrum: logarithmic magnitude scale for voltage units - Protocol: datetime stamp for SPI/I2C Spy Fixes 3.10.6 digilent.waveforms_beta_v3.10.6_64bit.exe Added: - Scope - access to digital channels from custom mathematic channels - digital measurements view Fixes 3.10.5 digilent.waveforms_beta_v3.10.5_64bit.exe digilent.waveforms_beta_3.10.5_amd64.deb digilent.waveforms_beta_3.10.5.x86_64.rpm Added: - Power Supplies for AD2: tracking, slider, min/max - Logic Analyzer: Measurements - Impedance Analyze: DC mode compensation - SDK VB wrapper, C# wrapper updated Fixed: - EExplorer Wavegen AM/FM index precision for sine 3.10.4 digilent.waveforms_beta_v3.10.4_64bit.exe Fixed: - decimal resolution in Export, Data and Event views 3.10.3 digilent.waveforms_beta_v3.10.3_64bit.exe digilent.waveforms_beta_v3.10.3.dmg digilent.waveforms_beta_3.10.3_amd64.deb digilent.waveforms_beta_3.10.3.x86_64.rpm Added: - UART format option (binary, decimal...) - SDK I2C without clock stretching - SDK examples: Digital_I2c_PmodAcl.py, Digital_I2c_PmodGyro.py - Spectrum Analyzer THDN measurement, THDp and THDNp in percentage units - Impedance Analyzer: - constant current, voltage, custom script for amplitude and resistance control - Option to disable mouse drag and wheel operations on plots - Impedance/Network Analyzer: averaging time - Wavegen: extended frequency option Changed: - special values (none, off) moved to end of the preset list 3.10.2 digilent.waveforms_beta_v3.10.2_64bit.exe digilent.waveforms_beta_v3.10.2_32bit.exe digilent.waveforms_beta_v3.10.2.dmg digilent.waveforms_beta_v3.10.2_mavericks.dmg digilent.waveforms_beta_3.10.2_amd64.deb digilent.waveforms_beta_3.10.2_i386.deb digilent.waveforms_beta_3.10.2.x86_64.rpm digilent.waveforms_beta_3.10.2.i686.rpm Added: - Impedance Analyzer - voltage, current and custom plots - edit Meter list - Resistance mode for Meter, Frequency DC option - step mode in Time view - Netowrk Analyzer - step mode in Time and FFT views - amplitude table and custom function Fixed: - Help minor fix - Protocol SPI and I2C Sensor rate improvement - StaticIO button lock 3.8.22 digilent.waveforms_beta_v3.8.22_64bit.exe digilent.waveforms_beta_v3.8.22_32bit.exe Added: - Impedance differential setup, W1-C1P-DUT-C1N-C2-R-GND 3.8.21 digilent.waveforms_beta_v3.8.21_64bit.exe digilent.waveforms_beta_v3.8.21_32bit.exe digilent.waveforms_beta_v3.8.21.dmg digilent.waveforms_beta_3.8.21_amd64.deb digilent.waveforms_beta_3.8.21_i386.deb digilent.waveforms_beta_3.8.21.x86_64.rpm digilent.waveforms_beta_3.8.21.i686.rpm Added: - data property for impedance/network channels. - Impedance.Resistor.reference property - instruments accessible without index in Script tool like Scope. Fixes... 3.8.20 digilent.waveforms_beta_v3.8.20_64bit.exe Added: - Logger function access to other channels value, average, min, max - Script access to Logger channel set data property, getting average, minimum, maximum Fixed: - Logger Show/Maximum - Script Protocol.I2C.Clear() function 3.8.18 digilent.waveforms_beta_v3.8.18_64bit.exe digilent.waveforms_beta_v3.8.18_32bit.exe digilent.waveforms_beta_v3.8.18.dmg Added: - Network Analyzer - logarithmic scale and percentage unit - spectrum measurements: Carrier, THD+N, THD, HD# - FFT view - Averaging option 3.8.17 digilent.waveforms_beta_v3.8.17_64bit.exe digilent.waveforms_beta_v3.8.17_32bit.exe digilent.waveforms_beta_v3.8.17.dmg digilent.waveforms_beta_3.8.17_amd64.deb digilent.waveforms_beta_3.8.17_i386.deb digilent.waveforms_beta_3.8.17.x86_64.rpm digilent.waveforms_beta_3.8.17.i686.rpm Added: - Scope - persistence support for smooth curve and min/max sampling - custom math - current value in custom math function, can be used for averaging - initialization code for integration purposes - examples - unit presets for: ohm, degree, VAC, AAC - Spectrum - Import/Export samples for Traces - trace information option - Range option to adjust all the scope input ranges - Network and Spectrum - Script support for set magnitude property - Step size and steps per decade settings - Network Analyzer - custom plots: THD, HD2, HD3 - Protocol - I2C/Spy glitch filter based on frequency setting - Device options - On Close: Run (keep running), Stop, Shutdown - USB Power: Always ON or Stop with AUX for AD2 - USB Limit: USB current limitation AD1,2 - Audio Output: AD1, 2 - WaveForms SDK FDwfParamSet/Get, FDwfDeviceParamSet/Get - DwfParamOnClose, DwfParamUsbPower, DwfParamLedBrightness, DwfParamAudioOut, DwfParamUsbLimit - Notes toolbar show/hide option - on/off icon for toggle buttons: supply enable, network analyzer reference... - show entire capture button Changed: - renewed mouse wheel, drag and key (left,right,up,down) operation on plots and axis Fixed: - EExplorer output glitch during first device connection - NI VI crash when initializing without device connected - Scope XY plot 3.8.11 digilent.waveforms_v3.8.11_64bit.exe digilent.waveforms_v3.8.11_32bit.exe digilent.waveforms_v3.8.11.dmg digilent.waveforms_3.8.11_amd64.deb digilent.waveforms_3.8.11_i386.deb digilent.waveforms_3.8.11.x86_64.rpm digilent.waveforms_3.8.11.i686.rpm Added: - Digital Discovery: - LED brightness option - Logic Analyzer - ASCII format for: Bus, SPI, I2C, I2S - Format option for I2C - Logic Analyzer and Patterns - Line Color option - Protocol - Format option for SPI and I2C: Hexadecimal, Decimal, Binary, ASCII - Plot Width option in application settings Changed: - drawing quality improvement for thicker lines - color dialog buttons renamed to Close and Reset 3.8.9 digilent.waveforms_v3.8.9_64bit.exe digilent.waveforms_v3.8.9_32bit.exe digilent.waveforms_v3.8.9.dmg digilent.waveforms_3.8.9_amd64.deb digilent.waveforms_3.8.9_i386.deb digilent.waveforms_3.8.9.x86_64.rpm digilent.waveforms_3.8.9.i686.rpm Added: - WF/Settings/Options: Locale with System or English US regional option, export and import options - SDK: FDwfParamSet/Get function - Scope: measurement resolution Fixed: - minor issues 3.8.8 digilent.waveforms_v3.8.8_64bit.exe digilent.waveforms_v3.8.8_32bit.exe digilent.waveforms_v3.8.8.dmg Added: - WF SDK: - examples updated to be Python v3 compatible - FDwfAnalogImpedance functions for impedance/network analysis - Protocol: CAN receiver filter by ID - Impedance: Export information about amplitude and offset Fixed: - WF SDK: FDwfDigitalSpi functions read MISO/RX 3.8.7 digilent.waveforms_v3.8.7_64bit.exe Fixed: - Scope: save/load of coefficients for custom Math channel filter 3.8.6 digilent.waveforms_v3.8.6_64bit.exe digilent.waveforms_3.8.6_amd64.deb Added: - Export: Wavegen and Supplies information added to Scope, Spectrum, Impedance, Network export comments Fixed: - Script Tool.exec timeout - CAN high polarity option in Protocol tool and WF SDK 3.8.5 digilent.waveforms_v3.8.5_64bit.exe Added - Script functions: getSaveFile, getOpenFile, getDirectory - Scope: multiple scales, zero offset - Notes view - Export options: notes, header as comment - Help tab: floating/undock option, find with highlight Fixed: - Impedance Analyzer frequency scale in export 3.7.22 digilent.waveforms_v3.7.22_64bit.exe digilent.waveforms_v3.7.22_32bit.exe digilent.waveforms_v3.7.22.dmg digilent.waveforms_3.7.22_amd64.deb digilent.waveforms_3.7.22_i386.deb digilent.waveforms_3.7.22.x86_64.rpm digilent.waveforms_3.7.22.i686.rpm Added - Scope/Logic View/Logging picture format - Script: - Export function for instruments - access to Protocol/UART/RX using Receiver, Receive and ReceiveArray functions, SendArray Fixed - Scope edge trigger position for all devices, when only one or two samples are above the threshold - other minor fixes 3.7.21 digilent.waveforms_v3.7.21_64bit.exe digilent.waveforms_v3.7.21_32bit.exe digilent.waveforms_3.7.21_amd64.deb digilent.waveforms_3.7.21_i386.deb digilent.waveforms_3.7.21.x86_64.rpm digilent.waveforms_3.7.21.i686.rpm Added - Wavegen dynamic configuration, adjustments without restarting the generator - SDK support for CAN bus TX, RX - more detail in Spectrum, Network and Impedance Analyzer export comments - import data orientation option Fixed - Network Analyzer Meter export and copy - Data Logger quick measurements - other fixes and optimizations 3.7.19 digilent.waveforms_v3.7.19-2_64bit.exe digilent.waveforms_v3.7.19-2_32bit.exe digilent.waveforms_v3.7.19.dmg digilent.waveforms_3.7.19-2_amd64.deb digilent.waveforms_3.7.19-2_i386.deb digilent.waveforms_3.7.19-2.x86_64.rpm digilent.waveforms_3.7.19-2.i686.rpm Added: - Logic I2S Show channel option - SDK functions for UART, SPI, I2C master and UART receiver Changed: - OS-X rollback to FTDI driver 1.2.2 Fixed: - Impedance Analyzer: save/load of views positions - other fixes and optimizations 3.7.15 digilent.waveforms_v3.7.15_64bit.exe digilent.waveforms_v3.7.15_32bit.exe Added: - Logic Analyzer: position (Nth word) option for SPI trigger on value - Impedance: Nyquist plot; settle time, minimum periods options - Wavegen, Network/Impedance Analyzer: external Amplification option - Tabbed/Docking window switching from main window Changed: - lower frequency limit for Scope, AWG, Network, Impedance Fixed: - 10ns delay in Logic Analyzer Sync and Protocol interface - Sound Card device CPU usage 3.7.14 digilent.waveforms_v3.7.14_64bit.exe digilent.waveforms_v3.7.14_32bit.exe Added: - Protocol I2C ACK/NAK last read byte option Changed: - Windows XP, Vista compatible FTDI driver in 32bit installer 3.7.13 digilent.waveforms_v3.7.13_64bit.exe digilent.waveforms_v3.7.13_32bit.exe digilent.waveforms_v3.7.13.dmg digilent.waveforms_3.7.13_amd64.deb digilent.waveforms_3.7.13_i386.deb digilent.waveforms_3.7.13.x86_64.rpm digilent.waveforms_3.7.13.i686.rpm Added: - Sound Card device of the computer can be used as Scope and Wavegen - Scope sampling clock for Electronics Explorer - Logic Analyzer data compression for recording, for Electronics Explorer - Scope and Wavegen support for 4th device configuration of Analog Discovery 1 & 2 - Scope Logging Repeat option - Scope Audio view: Stereo, Tempo options - MacOS option for application menu 3.7.12-2 digilent.waveforms_v3.7.12-2_64bit.exe Fixed: - Analog Discovery 2 configuration file descriptions 3.7.12 digilent.waveforms_v3.7.12_64bit.exe digilent.waveforms_v3.7.12_32bit.exe Added: - Scope sampling clock under time options, for Analog Discovery 1 & 2. The trigger IOs can be used as sample clock with delay and edge options. - Logic Analyzer data compression for recording, for Analog Discovery 1 & 2 Changed: - Windows installer: - embedded prerequisites: Windows Installer, Visual C++ Redistributable 9 32/64bit, 12 64bit - split installer for 32bit and 64bit WF applications, but the included WF runtime for custom applications support both architectures Fixed: - Logic Analyzer UART frame error threshold 3.7.10 digilent.waveforms_v3.7.10.exe Added: - Spectrum Analyzer Markers Fixed: - SDK Electronics Explorer enumeration - Scope Math channel unit presets 3.7.9 digilent.waveforms_v3.7.9.exe Fixing: - Logic Analyzer Event view double click for signals 3.7.8 digilent.waveforms_v3.7.8.exe Changed: - Impedance Analyzer: - view names - solid line for magnitude Fixed: - Impedance Analyzer admittance |Y| value 3.7.7 digilent.waveforms_v3.7.7.exe Added: - Scope and Logic trigger detector for trigger source Fixed: - warning message when connecting to EExplorer - Patterns trigger on Digital Discovery.
  7. 2 points

    Increasing the clock frequency to 260 MHz

    Hi, reading between the lines of your post, you're just "stepping up" one level in FPGA design. I don't do long answers but here's my pick on the "important stuff" - Before, take one step back from the timing report and fix asynchronous inputs and outputs (e.g. LEDs and switches). Throw in a bunch of extra registers, or even "false-path" them. The problem (assuming this "beginner mistake") is that the design tries to sample them at the high clock rate. Which creates a near-impossible problem. Don't move further before this is understood, fixed and verified. - speaking of "verified": Read the detailed timing analysis and understand it. It'll take a few working hours to make sense of it but this is where a large part of "serious" design work happens. - Once the obvious problems are fixed, I need to understand what is the so-called "critical path" in the design and improve it. For a feedforward-style design (no feedback loops) this can be systematically done by inserting delay registers. The output is generated e.g. one clock cycle later but the design is able to run at a higher clock so overall performance improves. - Don't worry about floorplanning yet (if ever) - this comes in when the "automatic" intelligence of the tools fails. But, they are very good. - Do not optimize on a P&R result that fails timing catastrophically (as in your example - there are almost 2000 paths that fail). It can lead into a "rabbit's hole" where you optimize non-critical paths (which is usually a bad idea for long-term maintenance) - You may adjust your coding style based on the observations, e.g. throw in extra registers where they will "probably" make sense (even if those paths don't show up in the timing analysis, the extra registers allow the tools to essentially disregard them in optimization to focus on what is important) - There are a few tricks like forcing redundant registers to remain separate. Example, I have a dozen identical blocks that run on a common, fast 32-bit system clock and are critical to timing. Step 1, I sample the clock into a 32-bit register at each block's input to relax timing, and step 2) I declare these register as DONT_TOUCH because the tools would otherwise notice they are logically equivalent and try to use one shared instance. This as an example. - For BRAMs and DSP blocks, check the documentation where extra registers are needed (that get absorbed into the BRAM or DSP using a dedicated hardware register). This is the only way to reach the device's specified memory or DSP performance. - Read the warnings. Many relate to timing, e.g. when the design forces a BRAM or DSP to bypass a hardware register. - Finally, 260 MHz on Artix is already much harder than 130 MHz (very generally speaking). Usually feasible but you need to pay attention to what you're doing and design for it (e.g. a Microblaze with the wrong settings will most likely not make it through timing). - You might also have a look at the options ("strategy") but don't expect any miracles on a bad design. Ooops, this almost qualifies as "long" answer ...
  8. 2 points
    Thinking of which... actually I do have a plain-Verilog FIFO around from an old design. It's not a showroom piece but I think it did work as expected (whatever that is...) For 131072 elements you'd set ADDRBITS to 17 and DATABITS to 18 for 18 bit width. module FIFO(i_clk, i_reset, i_push, i_pushData, i_pop, o_popAck, o_popData, o_empty, o_full, o_error, o_nItems, o_nFree); parameter DATABITS = -1; parameter ADDRBITS = -1; localparam ADDR_ZERO = {{(ADDRBITS){1'b0}}}; localparam ADDR_ONE = {{(ADDRBITS-1){1'b0}}, 1'b1}; localparam DATA_X = {{(DATABITS){1'bx}}}; input wire i_clk; input wire i_push; input wire i_reset; input wire [DATABITS-1:0] i_pushData; input wire i_pop; output reg o_popAck = 1'b0; output wire [DATABITS-1:0] o_popData; output reg o_error = 1'b0; output wire [31:0] o_nItems; output wire [31:0] o_nFree; output wire o_empty; output wire o_full; reg popAckB = 1'b0; reg [DATABITS-1:0] mem[((1 << ADDRBITS)-1):0]; reg [ADDRBITS-1:0] pushPtr = ADDR_ZERO; reg [ADDRBITS-1:0] popPtr = ADDR_ZERO; reg [DATABITS-1:0] readReg = DATA_X; reg [DATABITS-1:0] readRegB = DATA_X; wire [ADDRBITS-1:0] nextPushPtr = i_push ? pushPtr + ADDR_ONE : pushPtr; wire [ADDRBITS-1:0] nextPopPtr = i_pop ? popPtr + ADDR_ONE : popPtr; assign o_popData = o_popAck ? readReg : DATA_X; // === items counter === // note: needs extra bit (e.g. 4 slots may hold [0, 1, 2, 3, 4] elements) reg [ADDRBITS:0] nItems; assign o_nItems = {{{31-ADDRBITS-1}{1'b0}}, nItems}; assign o_nFree = (1 << ADDRBITS) - nItems; localparam NITEMS_ONE = {{(ADDRBITS){1'b0}}, 1'b1}; assign o_empty = nItems == 0; assign o_full = nItems == {1'b1, {{ADDRBITS}{1'b0}}}; always @(posedge i_clk) begin // === preliminary assignments === readRegB <= DATA_X; popAckB <= 1'b0; case ({i_push, i_pop}) 2'b10: nItems <= nItems + NITEMS_ONE; 2'b01: nItems <= nItems - NITEMS_ONE; default: begin end endcase o_error <= (i_push && ~i_pop && o_full) || (i_pop && o_empty); // === output register (delay 1) === o_popAck <= popAckB; readReg <= readRegB; pushPtr <= nextPushPtr; popPtr <= nextPopPtr; if (i_push) mem[pushPtr] <= i_pushData; if (i_pop) begin readRegB <= mem[popPtr]; popAckB <= 1'b1; end if (i_reset) begin pushPtr <= ADDR_ZERO; popPtr <= ADDR_ZERO; o_error <= 1'b0; o_popAck <= 1'b0; popAckB <= 1'b0; readReg <= DATA_X; readRegB <= DATA_X; nItems <= 0; end end endmodule
  9. 2 points

    Genesys 2 DDR Constraints

    Hi JColvin, I am definitely not using ISE. I think JPeyron had it correctly. I didn't have my board.Repopaths variable set and so the project wasn't finding the board files. Once I set this variable as suggested, the pin mapping and IO types were auto populated as expected. Kudos, Sean
  10. 2 points
    True. Zygot believes that making you work for knowledge is kinder than giving you solutions that can be used to mindlessly resolve your problem of the hour.... it's just a different philosophical bent...
  11. 2 points

    Pmod DA3 clocking

    It looks to me like DA3_WriteSpi() was adapted from code for a different device and has vestigial and incorrect code. Reviewing the AD5541A datasheet, several things stand out There is only a single register in the chip so there is no need for the u8 reg parameter. There is no need for a"config byte" to be sent before the data. The transfer is always 16 bits so there is no need to allow for arbitrary length data quoting from the datasheet "Input data is framed by the chip select input, CS. After a high-to-low transition on CS, data is shifted synchronously and latched into the serial input register on the rising edge of the serial clock, SCLK. After 16 data bits have been loaded into the serial input register, a low-to-high transition on CS transfers the contents of the shift register to the DAC register if LDAC is held low". Reviewing the PmodDA3 schematic, the ~LDAC signal is softly pulled to ground with a 10K resistor. So there is no need to explicitly toggle ~LDAC. What all this means is DA3_WriteSpi could be simplified to something like void DA3_WriteSpi(PmodDA3 *InstancePtr, u16 wData) { u8 bytearray[2]; bytearray[0] = ((wData & 0xFF00) >> 8); bytearray[1] = (wData & 0xFF); XSpi_Transfer(&InstancePtr->DA3Spi, bytearray, 0, sizeof(bytearray)); } You would then call it passing in just the instance pointer and the value you want to write to the DAC. u16 dacValue = 1234; DA3_WriteSpi(&myDevice, dacValue); I do not have a PmodDA3 on my bench so I cannot verify the function works, You can give it a try and let us know how it goes.
  12. 2 points

    Pin Mapping for JTAG-SMT3-NC

    Hi @RussGlover, I apologize for the delay; the details you are looking are as follows: TCK - ADBUS0 TDI - ADBUS1 TDO - ADBUS2 TMS - ADBUS3 OEJTAG - ADBUS7 OESRSTN - ACBUS4 Let me know if you have any more questions. Thanks, JColvin
  13. 2 points

    Pmod DA3 Pinout

    That is one of the conventions commonly used to indicate an Active Low signal. So in this case, you pull Chip Select low when you want to access the chip. After you have toggled in all the data bits on the DIN line, you pull LDAC low. The Pmod DA3 reference manual has a link to the D/A chip's datasheet. That is the best first place to look for information on the device's function. The required signal timings are on page 5 of the datasheet.
  14. 2 points
    @Ahmed Alfadhel If you installed Vivado then you also installed the Xilinx Document Navigator. If you are serious about developing with FPGA devices you need to know how to find and access the plethora of documents that your vendor provides in order to use their devices properly. Check the box for 7 Series devices to see the list of reference manuals, User's Guides, Datasheets etc. From there you can add all relevant documents to your search and keep up to date. Do the same for ISE or Vivado tools. This is where everyone needs to start their Xilinx FPGA journey. Xilinx makes it easier than other FPGA vendors to obtain knowledge.
  15. 2 points
    The answer is yes, that fixed it! Thank you so much! The odd thing is that I tried this in one of my attempts and put it back to QSPI as it didnt work. Regardless thank you so very much for walking me through this. all looks good now:
  16. 2 points
    So the picture that you post of a (relatively) gigantic scope probe clip resting on a fairly small FPGA device in a BGA package is a way of making a statement. It might also be viewed as a picture that might be making a statement to you. I routinely use an LED to verify that my design is at least being clocked properly. Make a 32-bit counter and connect bit 26 or so to an obuf driving one of the boards LEDs. You can get an approximation of a 1 blink/s LED rate with a little math depending on the clock rate and the chosen counter bit. For me the clock rate of interest isn't the external clock coming into the FPGA but some clock output of an MMCM or PLL that I'm using for my design. If the LED is blinking then I at least know that something is alive in my design. You've got to be careful with those large scope probe grabbers around fine pitch components. I prefer to bring out a few debug versions of particular signals of interest to a PMOD and connect that to a scope probe ( the PMOD has DGND pin(s) ). You still have to exercise some caution with the ground clip on your scope probe as it's easy to short an adjacent pin to ground and ruin your day. It would be very useful if Digilent provided GND test points, or at least holes for test points, in an area of their boards for scope probing. The safest thing might be to stick a pin into the GND receptacle of one PMOD connector and probe on signals in another. Insulation stripped off suitably sized wires can help as well to keep ground clips from accidents. It's really easy to have that ground clip pop off whatever it's connect to and bounce around on exposed parts of your board; nothing good will come of that. I limit scope probing to when it's necessary. There are usually safer ways to evaluate signals in your FPGA design. Lastly, you should understand that its very easy to get a false impression of what a signal looks like, especially with normal scope probe ground clips. Think Heisenberg.
  17. 2 points

    Hdmi out from zybo

    Try adding this: &i2c0 { clock-frequency = <100000>; status = "okay"; }; Here: <petalinux_project>/project-spec/meta-user/recipes-bsp/device-tree/files/system-user.dtsi -Ciprian
  18. 2 points

    Cmod S6 - Multilayer?

    You might go to Texas Instruments' site (or AD or both) and find documentation for some $500 high frequency ADC or DAC eval board as example to study.. There's nothing wrong with copper planes, generally. Free-standing structures (such as non-connected filler polygons) can be bad, if they resonate. So are loops if the driving wire spans an area together with the GND return wire (for which the ground plane is an obvious solution). The worst resonators have high quality factor meaning loose coupling meaning it can be surprising how the energy managed to couple in. There's no such thing as too many ground vias... Note, your ground plane can do very interesting things in combination with the metal box it's in (resonant cavity) but that's a different story.
  19. 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.
  20. 2 points
    And.... I have this sense that if you keep describing what you did you will answer your own question. I don't have enough information yet to help. [I confess that I haven't bothered to read through your code] Verbalizing problems, if you go into enough detail, is often a fairly reliably way to resolve them. Sometimes it helps to have someone throw in a good question or two.
  21. 2 points
    You are not wrong - but for that device ID the tooling will not let you use all the LUTs present on the silicon die. It is a somewhat artificial restriction, and might have some implications for the power and thermal properties of the package (e.g. a smaller package may not be able to dissipate the heat).
  22. 2 points
    Hi @aliff saad, Welcome to the forums. Here is the resource center for the PmodNAV. Here is a completed INO file, basically a main file, for the PmodNAV and an Arduino. The error is stating that LSM9DS1 is not assigned to a data type I.E. int, char... or in the case of the INO it is a class. Did you also download the SparkFun LSM9DS1 Arduino Library and add the src files to your project? cheers, Jon
  23. 2 points
    Hi, Abdul, Here are my notes/recommendations: 1. Open your block diagram in Vivado where you created BRAM configuration and then check the address editor. You should see whether the BRAM address was assigned. If you find assigned see axi_bram_ctrl_0 OffsetAdress and the Range then the BRAM was created and mapped to the memory. 2. Writing and reading from BRAM requires a clock signal. Check Xilinx templates for BRAM which you can access inside the Vivado. I am not sure that the code you've used to write into BRAM does anything. 3. You don't use an absolute address in your HDL when BRAM created in Vivado. Vivado maps the address 0x4000_0000 to 0. So you can start from the address 0 and it will be the lowest address of the BRAM. If your don't use Vivado then you will need to define your block in HDL and include addresses, and many other parameters. 4. The C-code in SDK should use BRAM address from the file parameters.h. You just need to use XPAR_AXI_BRAM_CTRL_0_S_AXI_BASEADDR as the begining of the BRAM address space. 5. You can treat BRAM as RAM meaning that all read/write operators are the same. For example you can copy BRAM content into the RAM: for(i = 0 ; i < BRAM_SIZE ; i++) *(destination + i) = *(source + i); where source = XPAR_AXI_BRAM_CTRL_0_S_AXI_BASEADDR Disclaimer: always read documentation, whatever you find on Internet might not be correct. Good luck!
  24. 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.
  25. 2 points
    Hi @Ben B, Regarding your question on using Zybo Z7-20 to capture HDMI signals. It is possible and using UIO is also an option, but because we are using the VDMA to get the Video signal it's better to use a DMA driver. Unfortunately Xilinx does not provide a complete DMA driver for any of their DMA IPs, therefore I have been using this DMA driver which includes the VDMA functionality as well. To make things as easy as possible, I generated a example project for you with the VDMA used to capture video streams and OpenCV functions to write a *.bmp file. What you need to do in order to get it working is: 1. load the HDMI2BMP.elf to /home/root on your rootfs portion of your board 2. after the board boots you need to load the axi_dma_driver root@Zybo-Z7-20:~# insmod /lib/modules/4.9.0-xilinx-v2017.4/extra/xilinx-axidma.ko 3. run the HDMI2BMP.elf This will generate a test.bmp in /home/root with the captured image. The source file for the app is in the SDK folder. Changes which I had to do to the original petalinux project are: - create a new module in petalinux petalinux-create -t modules -n xilinx-axidma --enable - copy the necessary file to Petalinux-Zybo-Z7-20/Zybo-Z7-20/project-spec/meta-user/recipes-modules/xilinx-axidma/files and update the MAKE file and the xilinx-axidma.bb - update the system-user.dtsi in /Petalinux-Zybo-Z7-20/Zybo-Z7-20/project-spec/meta-user/recipes-bsp/device-tree/files - write the demo program Hope this helps. -Ciprian Zybo-Z7-20-HDMI-RX_peta.zip
  26. 2 points
    >> having about 60uF of ceramic decoupling goodness Maybe it's even more a question of ESR than capacitance. Ceramic if money doesn't matter (e.g. Mouser: 22 µF: €4..6). The typical solution are staggered capacitors, with a quick look at the datasheet for the self resonance frequency in the impedance curve. I do this for RF (try to get a quality short at n GHz...) but if I had to make a blind guess, I'd use two orders of magnitude, e.g. 10 µ, 100n, 1n and with a nervous glance at my Voodoo doll, 10p. The CMOD A7 is reported quite frequently (possibly because it's one of the most attractive boards) but I can tell that I've run into the same issues with FTDI's reference module for the 2232H. The chip just shuts down if it doesn't like what it sees on VCC. It took a long Friday night in the lab to prove without doubt that our system is sensitive to USB cables. We changed the design and shipped with non-detachable cable. Zero issues so far.
  27. 2 points
    HI @yottabyte, I realize (based on the time stamps) that you figured out the answer to your question before you got a response, but do you mind posting your original question and what you found out so any future users with a similar question would be able to see the answer you (and xc6lx45) found out? Thanks, JColvin
  28. 2 points


    >> Is that solution Will run? I suspect you mean crosscorrelation, and no, it will most likely not work. Maybe you'll save yourself much pain if you prototype the algorithm first in software. It doesn't need to be real time. E.g. get freeware Octave and use the audioread() function. Be sure to use two independent recordings for reference and simulated microphone input.
  29. 2 points
    You're welcome! I am glad it is working. Yes, this thread should help others trying to run the Pcam 5C demo on Zybo Z7. Best Regards, Ionut.
  30. 2 points

    AD2 over voltage :-(

    Hi @peter taylor This was a ferrite between the Analog Discovery and USB ground. Supposed to filter noise from USB cable/PC which acted as a fuse... You can solder a simple short instead this ferrite. Hopefully only this was damaged. Be careful. The devices and circuits should have the same ground. The AD ground is connected to the PC ground over the USB cable.
  31. 2 points

    Nexys Video "Feet"

    https://www.fastenal.com/products/details/0146057 https://www.fastenal.com/products/details/28783
  32. 2 points

    Zynq book - tutorial 5 Zybo Z7

    Hi @n3wbie, Th working project is attached. what you have to take in to account when using this audio codecs with Digilent products is that you need to configure the codec (using I2C) as well as receive the samples using I2S IP core. Basically one is for the control of the codec and the other one is to receive the samples. I have written a small driver for both the I2S core and the I2C SSM2603 which is in the source files of the SDK project (in the sdk folder) which configures the registers for the codec and I2S IP core; the documentation for the codec can be found here. The IP core has not yet been documented which is the main reason we have not added it to the Digilent vivado-ip library, but it needs a 100MHz input for it to be able to synthesize the 12.228 MHz MCLK and the subsequent clocks for the I2S protocol. The demo project reads the buttons and based on the ones you press it will: BTN0 - Record 1s BTN1 - Set Mic input BTN2 - Set Line In input BTN3 - Playback 1s The project is not really optimized so it uses a variable "RecSamples", allocated to the stack memory which holds the recorded samples(48000 samples representing 1s at a 48KHz sampling rate) and it is also used fro play back, so don't press play back before record. The rest should be easily traceable from the comments in the driver and the main source code. If you have any other questions feel fr to ask. Ciprian ZyboZ7Audio.zip
  33. 2 points

    Diving in

    ... a slightly longer answer, if anybody is interested (analog mixing with square wave LO): One way is to look at the Fourier series of the square wave as a sum of sines at frequencies f, 3f, 5f, 7f, ... and to a lesser extent 2f, 4f, 6f from implementation imperfections. Then think of the mixer as linear multiplier, and use superposition (the distributive property of multiplication) for a*(b3+b5+b7+...) = a*b3+a*b5+a*b7+... Hint, if anybody wants to formally go through the math, it gets much less messy with cos(x) = (exp(ix)+exp(-ix))/2 aka DeMoivre. So you really get multiple frequency translations instead of one. What remains to be done is to manage the input signal energy at those frequencies I don't want, with a filter or narrow-band antenna. In the digital world, you'd always use a sine wave.
  34. 2 points
    Hi @spri Actually, the FDwfAnalogOutRunStatus returns not only the the remaining run but also the wait time. dwf.FDwfAnalogOutRunSet(hdwf, channel, c_double(2)) dwf.FDwfAnalogOutWaitSet(hdwf, channel, c_double(2)) dwf.FDwfAnalogOutRepeatSet(hdwf, channel, c_int(2)) dwf.FDwfAnalogOutConfigure(hdwf, channel, c_bool(True)) for i in range(10): sts = c_byte() sec = c_double() dwf.FDwfAnalogOutStatus(hdwf, channel, byref(sts)) dwf.FDwfAnalogOutRunStatus(hdwf, channel, byref(sec)) print("State: "+str(int(sts.value))+ " time left: "+ str(sec.value)) time.sleep(1) State: 7 time left: 1.99928738 // wait State: 7 time left: 1.00601063 State: 3 time left: 1.99434336 // run State: 3 time left: 0.97901375 State: 7 time left: 1.97874957 // wait State: 7 time left: 0.97872712 State: 3 time left: 1.9787507 // run State: 3 time left: 0.96878297 State: 2 time left: 0.0 // done @JColvin The *Get function return the configured value by *Set functions, like if you *Set the sample rate to 60MHz, the *Get will return the actually configured 50MHz, since the device can only do 100MHz, 50MHz, 33.3MHz...1uHz The *Status function return the monitorized information.
  35. 2 points

    Math on FFT traces

    Hi @lab!fyi The Script/Spectrum is added to the Help of beta version. Please use the Help of the application since this is the most up to date resource. https://forum.digilentinc.com/topic/8908-waveforms-beta-download/ You could use Ctrl+Space, code completion: https://forum.digilentinc.com/topic/15433-more-meta-data-wanted/?do=findComment&amp;comment=37724 Beside this the code is JavaScript: http://www.ecma-international.org/publications/standards/Ecma-262.htm https://www.w3schools.com/jsref/jsref_obj_math.asp For next software version added support to set trace data from script.
  36. 2 points

    Math on FFT traces

    Hi @lab!fyi 1. I think for your experiment you should use the Network Analyzer interface of the WaveForms application. Connect the Scope channel 1 to your filter input and channel 2 to the output. By default, the analyzer plots the magnitude and phase of channel 2 relative to 1. This will give the characteristics of your filter. In the NA under Wavegen gear menu select channel external (let you use external or custom wavegen control) and frequency extended (to let you use up to 50MHz). The Scope Math channel is performed on the time domain data not on the FFT. 2. The persistence view will be update with the next software version to handle curve interpolation option as well the min/max sampling.
  37. 2 points

    Basys 3 XADC

    Hi @Rohit kumar jain, To add to @BogdanVanca's post , here is an XADC demo for the Basys 3 that uses 4 analog inputs. Here is the GitHub releases for the XADC demo. thank you, Jon
  38. 2 points

    programming guide of zynq

    Hello @Ram, Please check this link : https://reference.digilentinc.com/learn/programmable-logic/tutorials/zybo-getting-started-with-zynq-server/start "This guide will provide a step by step walk-through of creating a Zynq based hardware design using the Vivado IP Integrator that will build over the Getting Started with Zynqguide by making use of the on-board Ethernet port and GPIOs for the Zybo FPGA board.". You can start from here, and use the same hardware logic but different type of application for uart, spi etc. Best Regards, Bogdan Vanca
  39. 2 points

    Zedboard Zynq 7000 XADC Header

    Hi @farhanazneen, I used the Analog Discovery 2 which has the 2x15 Flywires: Signal Cable Assembly for the Analog Discovery without issue. Each signal wire is 260mm± 20. thank you, Jon
  40. 2 points

    Where download 2015.4

    Hello @Bien, Please check this link : https://www.xilinx.com/support/download/index.html/content/xilinx/en/downloadNav/sdx-development-environments/archive.html. Best Regards, Bogdan Vanca
  41. 2 points
    Hello @Akshay Bhat, Please check this forum thread : . You will find in there a demo project for Zedboard that uses the Pmod interface to communicate with the the PMOD MTDS. You can use that project to provide your hardware platform. You are right, it's not an good idea to store 500 images on an sd card and try to dynamically swap them. My recommendation for you it's to go with this function: MTDS::TextOut(hds, xco, yco, cchText, rgchText). This function will draw the specified text string at the specified location. The only problem it's that you cannot change the char size. This feature it's not yet implemented into the mtds.h library. To see how exactly this function work, you can run MtdsTest22() from the same project. Also for more information please download the Arduino IDE from the fallowing link : https://reference.digilentinc.com/reference/software/mtds/start. Best Regards, Bogdan Vanca
  42. 2 points
    Hi Jon, Just want to give you an update. I got it working using the PL AXI Quad SPI controller after I fixed my IO constraints. And I did contact the Avnet support you mentioned above. Here is the thread if you are interested. Again thank you very much for your help on my project. -Iris
  43. 2 points

    Beginner DSP Projects

    Yes Dan he certainly would agree with your advice. Test, verify, test, verify. Let it be your mantra. Test and verify the main result that you are looking for. Test and verify all of the component parts ( particularly in logic ) in case you want to reuse any modules or components. Test and verify corner cases. Test and verify consistency of results between all of the implementations. For the logic implementation there will be more subtle and complicated aspects to consider and test for. Assume nothing. If all of this doesn't sound like fun ( I'm taking the long view by using that word) ... perhaps consider a different way to spend your free time. Oh, and I forgot to mention the most important part. Don't do it for self-defense. You can learn a lot more during the test and verification stages... you know, the part where most people have gone on to other things assuming that everything works, than you can learn during the basic design processes. Testing and verification generally requires another level of awareness to issues not obvious in the original conceptual stages. That's my experience.
  44. 2 points
    Nope, 32b is not supported by the Xilinx tools. But you are right what matters is not the architecture of the host but rather the guest, I messed that up 😕 You'll need this one.
  45. 2 points

    Analog Discovery 2 vs Raspberry Pi 3

    Hi @Phil_D @rprr The problem is that the USB IN packets/bytes are randomly lost/altered. I tried various kernel options, limiting the USB transfer rates but had no luck. The data corruption reduced from one in 1-60 seconds to one in 10-60 minutes, which it is still not good... It seems that the root of the problem is in the low level FTDI library, kernel or USB modules, or between them... The Analog Discovery is working fine with other SOCs but not with the RPi. I also notice issue with the USB keyboard I use with the RPi, time to time key presses are not received. You can find many similar RPi issues on the net: https://www.raspberrypi.org/forums/viewtopic.php?f=28&amp;t=5249&amp;sid=8839659cb92b7475fa196b2fad775d9f&amp;start=250 http://www.ftdicommunity.com/index.php?topic=40.0
  46. 2 points
    Hi, @sbobrowicz, Thank you for your reply. I found the cause of the problem and solved it. The ssm2603 driver was the cause. I found the link below with Google search. https://www.spinics.net/lists/alsa-devel/msg75416.html If you have a problem like me, try applying the patch above. (I am using Petalinux 2017.2 and Zybo-Z7-10. Linux version 4.9.0-xilinx) Thanks, Namio
  47. 2 points

    OpenCL on Zybo

    @mohammadhgh Unfortunately that platform does not support openCL. We hope to add it in a future release of the Zybo Z7 SDSoC platforms. It might be possible to add OpenCL support to that platform by just adding OpenCL as a "Supported Runtime". See UG1146 from Xilinx for info on how to do this.
  48. 2 points

    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.
  49. 2 points

    MMCM dynamic clocking

    Hey, something else I just saw when reading the clocking guide was: MMCM Counter Cascading The CLKOUT6 divider (counter) can be cascaded with the CLKOUT4 divider. This provides a capability to have an output divider that is larger than 128. CLKOUT6 feeds the input of the CLKOUT4 divider. There is a static phase offset between the output of the cascaded divider and all other output dividers. And: CLKOUT4_CASCADE : Cascades the output divider (counter) CLKOUT6 into the input of the CLKOUT4 divider for an output clock divider that is greater than 128, effectively providing a total divide value of 16,384. So that can divide a 600 MHz VCO down to 36.6 kHz.